Physics Work and Energy Problems

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Which equation is used to calculate work done?

Work = speed x time

Work = force x distance (correct)

Work = mass x acceleration

Work = energy x power

What is the SI unit of force?

Newton (correct)

Watt

Kilogram

Joule

Which concept involves resolving a force into its perpendicular components?

Centripetal Force Principle (correct)

Heat Transfer Mechanism

Newton's Law of Gravitation

Torque Calculation Method

What does the moment of force or torque represent?

Distance from pivot to line of action of force Signup and view all the answers

How is atmospheric pressure measured using the height of a liquid column?

By considering the weight of the liquid column Signup and view all the answers

What principle is involved in solving problems related to freely falling bodies?

Acceleration due to Gravity Principle Signup and view all the answers

Which of the following statements accurately describes the interpretation of displacement-time and velocity-time graphs for objects moving along a straight line?

A negative slope on a velocity-time graph indicates that the object is decelerating. Signup and view all the answers

Which of the following factors does NOT affect the friction between a vehicle's tires and the road surface?

The vehicle's color Signup and view all the answers

In the context of freely falling bodies, what is the acceleration due to gravity near the Earth's surface?

$10 \text{ m/s}^2$ Signup and view all the answers

Which of the following statements accurately describes Newton's laws of motion?

All of the above statements are correct. Signup and view all the answers

What is the definition of the moment of force or torque?

Torque = force × perpendicular distance from the pivot to the line of action of force Signup and view all the answers

Which of the following statements accurately describes the variation of the acceleration due to gravity (g) with altitude?

The value of g decreases with increasing altitude from the Earth's surface. Signup and view all the answers

What is the primary characteristic of heat of fusion and heat of vaporization?

They occur with a change in the phase of the substance, but without a change in temperature. Signup and view all the answers

Which of the following factors does NOT affect the transfer of heat through solid conductors?

The type of material the conductor is made of. Signup and view all the answers

In the context of thermal energy transfer, what is meant by a 'region of higher temperature'?

A region with a higher kinetic energy of particles. Signup and view all the answers

Which of the following equations correctly represents the motion of a body moving with uniform acceleration in a straight line?

v = u + at, s = ut + (1/2)at^2 Signup and view all the answers

According to the law of conservation of momentum, what happens to the total momentum of an isolated system before and after a collision?

The total momentum is always conserved. Signup and view all the answers

Which of the following statements correctly describes Pascal's law?

Pressure exerted on an enclosed fluid is transmitted equally in all directions. Signup and view all the answers

What is the work done by the girl in pulling the baby cart through 35 m while applying a force of 150 N?

$5,250 J$ Signup and view all the answers

Which of the following graphs correctly represents the motion of the ball thrown vertically upwards and returning to the ground after 10 seconds?

A parabolic graph with a maximum point at the highest point of the ball's trajectory Signup and view all the answers

Why are worn-out tires not safe to use on wet roads?

Worn-out tires have less tread depth, reducing the ability to grip the road and increasing the risk of hydroplaning on wet surfaces. Signup and view all the answers

What is the effect on a person sitting inside a bus when the bus takes a sudden turn to the left?

The person will be pushed towards the right side of the bus due to inertia. Signup and view all the answers

What is the formula for torque, and what is its SI unit?

Torque = $\tau = rF\sin\theta$, SI unit: Newton-meter (Nm) Signup and view all the answers

At what altitude would the value of 'g' (acceleration due to gravity) become one-ninth of its value at the Earth's surface?

Approximately 36,000 km above the Earth's surface Signup and view all the answers

What is the second equation of motion for a uniformly accelerated body?

$2as = v^2 - u^2$ Signup and view all the answers

According to the law of conservation of momentum, if an object of mass m1 moving with velocity u1 collides with another object of mass m2 moving with velocity u2, what is the expression for the recoil velocity of the gun after firing?

$v_r = \frac{m_2u_2 - m_1u_1}{m_1 + m_2}$ Signup and view all the answers

If a force F makes an angle with the x-axis, what are the perpendicular components of the force along the x and y axes?

F cos along x-axis, F sin along y-axis Signup and view all the answers

According to Newton's law of gravitation, if the mass of the Earth is M and the radius of the Earth is R, what is the expression for the mass of the Earth?

$M = \frac{gR^2}{G}$ Signup and view all the answers

According to Pascal's law, what is the principle behind the working of a hydraulic press, which is also known as a force multiplier?

Pressure exerted at any point in a confined incompressible fluid is transmitted equally in all directions. Signup and view all the answers