Physics 2022 Quiz Questions

Units of Measurement

• The unit of work is Joules (J)
• The unit of energy is Joules (J)
• The unit of specific heat capacity is J/kg°C
• The unit of measurement for pressure is Pascals (Pa)

Ultrasonic Distance Measurement

• The time taken for the ultrasonic impulse to travel to the obstacle and back is 2 x distance / speed of sound
• In this case, the distance is 66 meters, and the time taken is 400 ms

Specific Latent Heat

• The specific latent heat of fusion is expressed in J/kg
• It is the amount of energy required to change the state of 1 kg of a substance from solid to liquid

Pressure in Orlicka Dam

• The maximum depth of the Orlicka Dam is 70 meters
• The pressure at this depth is equal to 700 kPa plus the atmospheric pressure

Barometric Pressure

• Barometric pressure can be expressed in different units
• 1 bar is equal to 100 kPa, and 760 Torr is equal to 760 mmHg

Electric Charge

• A fully charged battery with a capacity of 4 Ah is discharged to half its capacity with a constant current of 50 mA
• The amount of charge lost is 1440 C

Gravitational Force

• The gravitational force between two objects decreases with an increase in distance
• If the distance between the objects is quadrupled, the gravitational force decreases by a factor of 16

Image Formation by Lenses

• A convex lens can form a real, inverted, and magnified image when the object is placed between the focal length and the lens
• The object distance must be greater than the focal length of the lens for this to occur

Light and Optics

• When light transitions from a vacuum to an optical medium, its frequency remains unchanged.
• The speed of light changes when it enters an optical medium.

Fluid Dynamics

• The magnitude of the buoyant force acting on a fully submerged object depends on the object's volume and the density of the fluid.
• The buoyant force does not depend on the object's density.

Radioactivity

• When a radioactive element emits a particle, it shifts one place to the left in the periodic table.
• The emitted particle is not an electron or a helion.

Energy and Work

• The unit of work is not Watt (W).
• The unit of work can be Joule (J), Watt-second (Ws), or Newton-meter (Nm).

Electromagnetic Spectrum

• The boundary between infrared and visible light corresponds to a wavelength of 760 nm.

Efficiency of Machines

• The efficiency of an electrical machine is given by the ratio of output power to input power.

Heating and Temperature

• When a heating element is connected to a voltage that is half the original value, its power output will decrease by a factor of four.
• The efficiency of a heating element is not directly proportional to the voltage.

Thermodynamics

• The unit of specific latent heat of fusion is J/kg.

Energy and Kinematics

• The energy released when an object falls from a height of 20 m is equal to 1600 J.
• The mass of the object can be calculated from the energy released.

Phase Transitions

• Boiling of a liquid occurs when the pressure of the saturated vapor in the liquid equals the surrounding pressure.

Radioactive Decay

• The half-life of a short-lived isotope can be calculated from the decrease in activity over time.
• The activity of the isotope decreases by a factor of 2 every half-life.