Q3 - GENERAL PHYSICS - DOCX VERSION (1) PDF Past Paper

1.​ If two resistors with resistances of 10 Ω and 20 Ω A. Rubbing involves contact, while induction are connected in series to a 30 V battery, and then does not require direct contact connected in parallel to the same battery, which of B. Induction tra...

1.​ If two resistors with resistances of 10 Ω and 20 Ω A. Rubbing involves contact, while induction are connected in series to a 30 V battery, and then does not require direct contact connected in parallel to the same battery, which of B. Induction transfers protons while rubbing the following statements is true about the total transfers neutrons current in the circuit? C. Rubbing creates charges, while induction destroys charges A. The total current in the series circuit will be D. Induction involves rubbing objects together to greater than in the parallel circuit. generate heat B. The total current in the series circuit will be the same as in the parallel circuit. 7.​ If the length of a wire is halved and its C. The total current in the parallel circuit will be cross-sectional area is doubled, how will the greater than in the series circuit. resistance of the wire change according to the D. The total current in both circuits will be zero. relationship R=ρ L/A? 2.​ When an object becomes charged by rubbing, A. The resistance will remain the same. what causes the charge transfer to occur? B. The resistance will double. C. The resistance will be halved. A. Protons moving between objects D. The resistance will be reduced by a factor of 4. B. Neutrons moving between objects C. Electrons transferring from one object to 8.​ What principle calculates the net electric field at a another point due to multiple charges? D. The objects sharing their charges equally A. Coulomb's law and the principle of charge 3.​ Which of the following best describes Kirchhoff's conservation Current Law (KCL)? B. The superposition principle, summing vector contributions from each charge A. The sum of the potential differences around any C. Gauss's law applied to point charges closed loop is zero. D. Subtracting the weaker charge field from the B. The total current entering a junction is equal stronger one to the total current leaving the junction. C. The total resistance in a parallel circuit is equal 9.​ According to the formula R=ρ L/A, which of the to the sum of the individual resistances. following statements is correct regarding the D. The total power dissipated in a circuit is equal relationship between resistance, length, and to the product of the total current and total voltage. crosssectional area of a wire? 4.​ Which of the following best describes charging by A. The resistance of a wire increases as its length induction? decreases. B. The resistance of a wire decreases as its A. Transferring charge by directly touching another crosssectional area increases. object C. The resistance of a wire increases as its B. Charging an object by rubbing it with another crosssectional area increases. material D. The resistance of a wire is independent of its C. Rearranging the charges in an object length and cross-sectional area. without direct contact D. Destroying charges by bringing an object near a 10.​ Two charges, q1=+2 C and q2=−3 C are placed 4 neutral body m apart. What is the correct approach to calculate the electric field at a point midway between them? 5.​ A wire's resistance is 8 Ω. If the length of the wire is doubled while the cross-sectional area is halved, A. Use Coulomb’s law to calculate the field due to how will the new resistance compare to the each charge and then add the magnitudes of the original resistance? fields directly. B. Use Coulomb’s law to find the field vectors A. The new resistance will be 16 Ω. due to each charge and add them using vector B. The new resistance will be 4 Ω. addition. C. The new resistance will be 32 Ω. C. Find the net charge and use Coulomb’s law to D. The new resistance will be 64 Ω. calculate the total field. D. Ignore the charges since the point is equidistant 6.​ What is the key difference between charging by from both. rubbing and charging by induction? 11.​ If the length of a wire is doubled and its crosssectional area is halved, how will the  resistance of the wire change according to the resistance in Ohmic materials, according to Ohm's formula for resistance R=ρ L/A, where ρ is the law? resistivity, L is the length, A is the cross-sectional area? A. The current is directly proportional to the voltage and inversely proportional to the A. The resistance will remain the same. resistance. B. The resistance will double. B. The current is inversely proportional to both the C. The resistance will quadruple. voltage and the resistance. D. The resistance will increase by a factor of 4. C. The voltage is directly proportional to the resistance and inversely proportional to the 12.​ A charge of an atom, q=+4 C is placed 6 m apart current. along a straight line. What is the magnitude of the D. The voltage is directly proportional to the net electric field? current and inversely proportional to the resistance. A. 9.99 x 10^8 N/C B. 9.0 x 10^8 N/C 18.​ You are designing an electronic device with a C. 9 x 10^8 N/C sensor that operates based on electric fields. Two D. 10 x 10^8 N/C small charged objects, q1=+5 μC, and q2=−3 μC, are placed 4 m apart on a straight line to create an 13.​ A light bulb has a resistance of 12 Ω. When electric field for the sensor. The sensor is located connected to a 24 V power supply, what is the at a point, which is 2 m from q1 and 2 m from q2. current flowing through the light bulb according to What is the net electric field experienced by the Ohm's law? sensor at this point? A. 1 A A) 5×10^4 N/C B. 2 A B) 4 × 10^4 N/C C. 12 A C) 1.8×10^4 N/C D. 24 A D) 2 × 10^4 N/C 14.​ Find the electrostatic force between charges of 19.​ A current of 0.25 A flows through a conductor for 2 +5.0 C and +3.0 C separated by a distance of 75 hours, and the same current flows through another m in a vacuum. conductor for 5 hours. Which conductor experiences a greater total charge transfer? A. 3.2 x 10^7 N B. 2.7 x 10^7 N A.The conductor with 0.25 A for 2 hours transfers C. 1.8 x 10^7 N more charge. D. 2.4 x 10^7 N B. The conductor with 0.25 A for 5 hours transfers more charge. 15.​ In an electrical circuit with a resistor made of C. Both conductors transfer the same amount of Ohmic material, the resistance is 10 Ω, and the charge. voltage across the resistor is 20 V. Using Ohm's D. The conductor with 0.25 A for 2 hours transfers law, what is the current flowing through the at no charge. resistor? 20.​ A charge q0=+1 μC is placed at the origin of a A. 0.5 A coordinate system. Two other charges, q1=+2 μC B. 2 A and q2=−3 μC are located at points (2 m, 0) and C. 20 A (0,3 m), respectively. Which of the following steps D. 200 A is incorrect in determining the net force on q0 due to q1 and q2 ? 16.​ Two charges of +8.0 C and -6.0 C attract each other with a force of 3.0 x 103 N in a vacuum. A) Calculate the force due to q1 on q0 using What is the distance between the charges? Coulomb's law. B) Calculate the force due to q2 on q0 using A. 4.3 x 10^7 m Coulomb's law. B. 1.6 x 10^7 m C) Add the magnitudes of the forces due to q1 C. 1.2 x 10^7 m and q2 directly without considering their D. 3.5 x x 10^7 m directions. D) Use vector addition (Pythagorean theorem) to 17.​ Which of the following best describes the calculate the net force on q0 by combining the x relationship between current, voltage, and and y components of the forces. 21.​ A current of 4 A flows through a conductor for 10 26.​ Two charged objects attract each other with a minutes. If the conductor is replaced and the certain force. If the charges on both objects are current is reduced to 2 A, but the time is increased doubled with no change in separation, what will to 30 minutes, which situation results in a greater happen to the force between them? total charge transferred? A. quadruples A. The situation with 4 A current for 10 minutes B. doubles transfers more charge. C. halves B. The situation with 2 A current for 30 minutes D. increases transfers more charge. C. Both situations transfer the same charge. 27.​ If the current in a circuit is doubled while keeping D. The situation with 4 A current for 10 minutes the time constant, what will happen to the total transfers less charge. charge transferred according to the equation Q= I × t? 22.​ Two point charges, +4 μC and −6 μC are placed 8 m apart. A third charge, +2 μC is located 3 m away A. The total charge will remain the same. from q1 and 5 m away from q2. What can be said B. The total charge will be halved. about the direction of the net force on q3 ? C. The total charge will double. D. The total charge will be quadrupled. A) The net force on q3 points toward q1. B) The net force on q3 points toward q2. 28.​ An air purifier uses an electric field to trap dust C) The net force on q3 points somewhere particles by charging them as they pass through a between q1 and q2 , depending on their region with a uniform electric field. If the dust relative force magnitudes. particles are modeled as tiny charged spheres and D) The net force on q3 is zero because the a Gaussian surface is imagined around one of charges cancel each other. these particles, which of the following statements is correct about the electric flux through the 23.​ A battery is connected to a resistor and a current Gaussian surface? of 0.5 A flows for 20 minutes. After 10 minutes, the current is increased to 1.0 A. What is the total A. The electric flux depends on the electric field charge transferred during these 20 minutes? strength generated by the air purifier. B. The electric flux depends only on the charge A) 10 C of the dust particle enclosed by the Gaussian B) 12 C surface. C) 15 C C. The electric flux depends on the radius of the D) 20 C Gaussian surface around the dust particle. D. The electric flux is zero because the charge is 24.​ When two charges exert forces simultaneously on small. a third charge, the total force acting on that charge 29.​ If the current in a circuit is constant and flows for a is the vector sum of the forces that the two longer period, what happens to the total charge charges would exert individually. This principle is transferred according to the equation Q=I × t? known as the _____. A. The total charge increases because the A. interference of charge charge is directly proportional to time. B. Coulomb’s principle B. The total charge decreases because the charge C. superposition of force is inversely proportional to time. D. superposition of electric field C. The total charge remains the same regardless of the time. 25.​ A current of 2 A flows through a conductor for 3 D. The total charge increases because the charge minutes. If the current is maintained for an is inversely proportional to time. additional 2 minutes, what will happen to the total charge transferred during these 5 minutes? 30.​ In photocopiers, a uniform electric field is used to distribute toner particles on a charged drum. If a A. The total charge transferred will increase to 10 toner particle carries a charge q=−5 μC, which of C. the following statements best describes the B. The total charge transferred will increase to electric flux through a Gaussian surface 12 surrounding the toner particle? C. The total charge transferred will decrease to 8 C. A. The electric flux depends on the total electric D. The total charge transferred will remain at 6 C. field created by the drum and the toner particle.  B. The electric flux is negative because the Suppose the capacitor is connected to a battery toner particle has a negative charge. that maintains a constant voltage of 10 V, and a C. The electric flux depends on the size of the dielectric with a dielectric constant of 2 is inserted. Gaussian surface around the toner particle. What will happen to the charge, capacitance, and D. The electric flux is positive because the drum voltage across the plates? creates a uniform electric field A. The capacitance increases to 10 µF, the charge 31.​ If the current in a circuit is 3 A and it flows for 5 remains the same, and the voltage decreases to 5 seconds, what is the total charge transferred V. during this time according to the equation Q=I × t? B. The capacitance increases to 10 µF, the charge increases to 100 µC, and the voltage A) 15 C remains at 10 V. B) 8 C C. The capacitance remains the same, the charge C) 3 C remains at 50 µC, and the voltage remains at 10 V. D) 5 C D. The capacitance increases to 10 µF, the charge remains at 50 µC, and the voltage remains at 10 V. 32.​ An electric field of 6 N/C on a flat surface with an area of 4 m2 is placed in the field. The surface is 36.​ Which of the following factors does not affect the oriented at different angles for the electric field, strength of the electric field created by a point and the electric flux through the surface is charge? calculated for each angle. Which of the following statements is true about the electric flux through A. The magnitude of the charge. the surface? B. The distance from the charge. C. The presence of other charges nearby. A. The electric flux is maximum when the D. The medium (material) surrounding the charge surface is oriented parallel to the electric field. B. The electric flux is zero when the surface is 37.​ A capacitor with a capacitance of 10 µF is charged perpendicular to the electric field. to 6 V, storing a charge of 60 µC. Suppose a C. The electric flux is the same for any orientation dielectric with a dielectric constant of 4 is inserted of the surface. while the capacitor is disconnected from the power D. The electric flux is minimal when the surface is supply. What will happen to the charge, oriented parallel to the electric field capacitance, and voltage across the plates? 33.​ What does the equation Q=I × t represent in terms A. The capacitance increases to 40 µF, the of electric current? charge remains the same at 60 µC, and the voltage decreases to 1.5 V. A. The total amount of charge passing through B. The capacitance increases to 40 µF, the charge a conductor in a given time. increases to 240 µC, and the voltage remains the B. The energy required to move a charge through same at 6 V. a conductor. C. The capacitance increases to 40 µF, the charge C. The force experienced by a charge in a remains the same at 60 µC, and the voltage conductor. remains the same at 6 V. D. The voltage required to move a certain amount D. The capacitance remains at 10 µF, the charge of charge through a conductor. remains the same at 60 µC, and the voltage increases to 24 V. 34.​ A spherical surface of r=5 m surrounds a point charge q=+2 μC. If the radius of the spherical 38.​ Which of the following correctly describes how the surface is doubled to r=10, how does the electric strength of the electric field changes when the flux through the surface change? distance from a point charge is doubled? A. The electric flux doubles because the surface A. The electric field strength doubles. area increases. B. The electric field strength is halved. B. The electric flux is halved because the radius C. The electric field strength is reduced by a increases. factor of four. C. The electric flux remains the same because D. The electric field strength remains unchanged. it depends only on the enclosed charge. D. The electric flux increases by a factor of four 39.​ Which of the following is a correct statement about because the radius increases. the direction of the electric field created by a positive point charge? 35.​ A capacitor with a capacitance 5 μF is charged to a voltage of 10 V, storing a charge of 50 µC.  A. The electric field points radially inward toward D. The electric potential is constant and the charge. independent of the distance from the charge. B. The electric field points radially outward from the charge. 44.​ Why are capacitors important in signal processing C. The electric field is tangent to the surface of a applications, such as in audio systems or radio sphere surrounding the charge. receivers? D. The electric field is parallel to the line connecting two positive charges. A. They prevent the loss of signal strength by amplifying weak signals. 40.​ What happens when a dielectric material is B. They filter out unwanted frequencies, inserted between the plates of a charged allowing only the desired signal to pass. capacitor? C. They act as resistors to control the current flow in the circuit. A. The capacitance increases, the charge on the D. They store energy and release it to keep the plates decreases, and the electric field remains the signal at a constant level. same. B. The capacitance increases, the charge on 45.​ What is the electric potential at a point halfway the plates remains the same, and the electric between two equal and opposite charges +Q and field decreases. −Q, separated by a distance? C. The capacitance decreases, the charge on the plates remains the same, and the electric field A. The electric potential is zero. increases. B. The electric potential is positive. D. The capacitance decreases, the charge on the C. The electric potential is negative. plates increases, and the electric field decreases. D. The electric potential is infinite. 41.​ Which of the following best describes the nature of 46.​ How do capacitors contribute to the functioning of the electric field between two parallel plates a filtering circuit in electronics? connected to a battery? A. Capacitors allow high-frequency signals to pass A. The electric field is uniform and points from through while blocking low-frequency signals. the positive plate to the negative plate. B. Capacitors store high-frequency signals and B. The electric field is radial and points away from prevent them from entering the circuit. the positive plate. C. Capacitors smooth out fluctuations in C. The electric field is non-uniform and points from voltage by storing and releasing charge. the negative plate to the positive plate. D. Capacitors store power and release it only D. The electric field is zero between the plates. when the circuit is turned off. 42.​ In a camera’s flash unit, capacitors are used to 47.​ store energy. Why are capacitors the preferred choice in this application? A. Capacitors can release the stored energy quickly to generate a high-intensity flash. B. Capacitors allow energy to be stored for a long time, ensuring the flash is ready whenever needed. C. Capacitors regulate power consumption to reduce energy usage. D. Capacitors amplify the energy to create a 48.​ Why are capacitors used in timing circuits, such as stronger flash. those in oscillators or clocks? A. To control the rate at which the circuit 43.​ Which of the following best describes the electric charges and discharges, determining the potential at a point due to a positive point charge? timing cycle. B. To reduce the power consumption of the circuit. A. The electric potential is always negative at all C. To store magnetic energy for short bursts of points. power. B. The electric potential decreases as the D. To increase the voltage of the circuit over time. distance from the charge increases. C. The electric potential increases as the distance 49.​ If the distance between two charges is doubled, from the charge increases. how does the electric potential energy of the system change?  A. The electric potential energy is doubled. B. The electric potential energy is halved. C. The electric potential energy is reduced by a factor of four. D. The electric potential energy remains unchanged. 50.​ Why are capacitors used in power supply circuits in electronic devices? A. To store and release electrical energy to smooth out fluctuations in voltage. B. To increase the total resistance in the circuit. C. To convert AC into DC. D. To store and discharge magnetic energy.