Question 1

A car accelerates uniformly from rest and reaches a velocity of 20 m/s in 5 seconds. What is the acceleration of the car?

Accepted Answer

Using the formula a = (v - u) / t, where v = 20 m/s, u = 0, and t = 5 s, we get a = 20/5 = 4 m/s².

Question 2

According to Newton's First Law of Motion, an object will remain at rest or in uniform motion unless acted upon by an external force. What is this property called?

Accepted Answer

Inertia is the property of matter that resists changes in motion or rest, which is exactly what Newton's First Law describes.

Question 3

A ball is thrown vertically upward with an initial velocity of 30 m/s. Taking g = 10 m/s², what is the maximum height reached by the ball?

Accepted Answer

Using h = u²/(2g), where u = 30 m/s and g = 10 m/s², we get h = 900/20 = 45 m.

Question 4

A force of 50 N is applied to an object with a mass of 10 kg. What is the acceleration produced in the object according to Newton's Second Law?

Accepted Answer

Using F = ma, we get a = F/m = 50/10 = 5 m/s².

Question 5

A car accelerates uniformly from rest and reaches a velocity of 20 m/s in 5 seconds. What is its acceleration?

Accepted Answer

Using the formula a = (v - u)/t, where v = 20 m/s, u = 0, and t = 5 s, we get a = 20/5 = 4 m/s².

Question 6

According to Newton's second law of motion, force is equal to the product of mass and acceleration. If a 2 kg object experiences a net force of 8 N, what will be its acceleration?

Accepted Answer

Using F = ma, where F = 8 N and m = 2 kg, we get a = F/m = 8/2 = 4 m/s².

Question 7

An object moves 50 meters in the first 5 seconds and 100 meters in the next 5 seconds. Which statement correctly describes its motion?

Accepted Answer

Since the distance covered in successive equal time intervals is increasing (50 m then 100 m), the object is accelerating uniformly.

Question 8

Which of Newton's laws of motion states that an object at rest remains at rest unless acted upon by an external force?

Accepted Answer

Newton's first law of motion defines the concept of inertia and states that an object maintains its state of rest or uniform motion unless an external force acts on it.

Question 9

A bus moving at 15 m/s applies brakes and comes to rest in 3 seconds. What is the deceleration of the bus?

Accepted Answer

Using a = (v - u)/t, where v = 0 m/s, u = 15 m/s, and t = 3 s, we get a = (0 - 15)/3 = -5 m/s² (deceleration of 5 m/s²).

Question 10

A car accelerates uniformly from rest and covers 100 m in 5 seconds. What is its acceleration?

Accepted Answer

Using s = ut + ½at² where u = 0, s = 100 m, t = 5 s: 100 = 0 + ½a(25), so a = 8 m/s².

Question 11

According to Newton's Second Law of Motion, if the same force is applied to two objects with masses 2 kg and 4 kg respectively, what is the ratio of their accelerations?

Accepted Answer

From F = ma, if force is constant, a ∝ 1/m; therefore a₁/a₂ = m₂/m₁ = 4/2 = 2/1 or 2:1.

Question 12

A ball is thrown vertically upward with an initial velocity of 20 m/s. Taking g = 10 m/s², what is the maximum height reached by the ball?

Accepted Answer

Using v² = u² - 2gh, at maximum height v = 0: 0 = (20)² - 2(10)h, so h = 400/20 = 20 m.

Agniveer Army GD Motion & Laws

Motion & Laws — Practice Questions