Laws Of Motion

If a body starts from rest, its initial velocity is:
1. Zero
2. Equal to its final velocity
3. Not sure
4. None of these
What is the momentum of a man of mass 75kg when he walks with a uniform velocity of 2 m/s?
1. 75 kg.m/s
2. 150 kg.m/s
3. 100 kg.m/s
4. 300 kg.m/s
When a toothpaste tube is sqeezed, it shape changes. The force responsible for this is an example:
1. Balanced forces
2. Centripetal forces
3. Unbalanced forces
4. Centrifugal forces
When we talk of a force acting on a body, it usually means:
1. Electrical force
2. Balanced force
3. Unbalanced force
4. Nuclear force
The inertia of an object tends to cause an object:
1. To increase its speed
2. To decrease its speed
3. To resist a change in its state of motion
4. To decelerate due to friction
When hanging carpet is beaten with a stick the dust particle starts coming out of it. This phenomenon can be best explained by making use of:
1. Newton's third law of motion
2. Newton's law of gravitation
3. Newton's first law of motion
4. Newton's second law of motion.
A passenger in a moving train tosses a coin which falls behind him. This shows that the motion of train is:
1. Accelerated
2. Uniform
3. Retarded
4. Along circular track
If we release a magnet held in our hand, it falls to the ground. The force which makes the magnet fall down is an example of :
1. Balanced force
2. Unbalanced force
3. Magnetic force
4. Mascular force
The inertia of a moving object depends on:
1. Momentum of the object
2. Speed of the object
3. Mass of the object
4. Shape of the object
When a rubber balloon held between the hands is pressed, its shape changes. This happens because:
1. Balanced forces act on the balloon
2. Unbalanced forces act on the baloon
3. Frictional forces act on the balloon
4. Gravitational forces act on the balloon
Which of the following effect cannot be produced by an unbalanced force acting on a body?
1. Change in speed of the body
2. Change in shape of body
3. Change in direction of motion of the body
4. Change in state of rest of the body
What force would be needed to produce an acceleration of $4 m / s^{2}$ in a ball of mass 6kg?
1. 24 newtons
2. 24 kg
3. 12 newtons
4. 1.5 newtons
What is the accelertation produced by a force of 12 newtons exerted on a mass of 3 kg?
1. $2 m / s^{2}$
2. $36 m / s^{2}$
3. $4 m / s^{2}$
4. 4 m/s
Calculate the force required to impart to a car having velocity of 30 m/s in 10 seconds starting from rest. The mass of the car is 1500kg.
1. 4500 kg
2. 500 N
3. 4000 N
4. 4500 N
The speed-time graph of a car is given alongside. The car wieghs 1000kg.
What is the braking force applied at the end of 5 seconds to bring the car to stop within one second?
1. - 15000 N
2. 15000 N
3. - 5000 N
4. 10000 N
The speed-time graph of a car is given along side.The car wieghs 1000 kg. What is the distance travelled by the car in the first two seconds?
1. 90 m
2. 7.5 m
3. 30 m
4. 15 m
A truck starts from rest and rolls down a hill with constant acceleration.It travels a distance of 400 m in 20 s. Find its acceleration. Find the force acting on it if its mass is 7 metric tones.
1. 14000 N
2. - 14000 N
3. 14000 kg
4. - 14000 N
A force of of 5 newtons gives a mass $m_{1}$ an acceleration of $8 m / s^{2}$ , and a mass $m_{2}$ an acceleration of $24 m / s^{2}$ . What acceleration would it give both the masses are tied together?
1. 6 m/s
2. $32 m / s^{2}$
3. $6 m / s^{2}$
4. $16 m / s^{2}$
Which would require a greater force?
a)
b) A 20 g mass at $2 m / s^{2}$
1. Accelerating a 10 g mass at $5 m / s^{2}$
2. A 20 g mass at $2 m / s^{2}$
3. Same force is required
4. Can't say
A bullet of mass 10 g is fired from a gun of mass 6 kg with a velocity of 300 m/s. Calculate the recoil velocity of the gun.
1. 0.5 m/s
2. 50 m/s
3. $0.5 m / s^{2}$
4. 1 m/s
The car A of mass 1500 kg, travelling at 25 m/s collides with another car B of mass 1000 kg travelling at 15 m/s in the same direction. After collision the velocity of car A becomes 20 m/s. Calculate the velocity of car B after the collision.
1. 22.5 m/s
2. 225 m/s
3. 82.5 m/s
4. None of these
Mass of a body is 5 kg. What iks its wieght?
1. 49 N
2. 49 kg
3. 5 kg
4. None of these
A bullet of mass 10 gram moving with a velocity of 400 m/s gets embedded in a freely suspended wooden block of mass 900 m/s. What is the velocity acquired by the block?
1. 20 m/s
2. 44 m/ss
3. 4.4 m/s
4. 5.6 m/s
The rocket works on the principle of conservation of:
1. Mass
2. Momentum
3. Energy
4. Velocity
When a ball is thrown vertically upwards, it goes through a distance of 19.6 m. Find the initial velocity of the ball and the time taken by it to rise to the highest point. (g = $9.8 m / s^{2}$ )
1. u = 19.6 m/s t = 2 s
2. u = 9.8 m/s t = 2 s
3. u = 19.6 m/s t = 4 s
4. u = 9.8 m/s t = 4 s
Calculate the force of gravitation due to earth on a ball of 1 kg mass lying on the ground. (Mass of earth = $6 \times 10^{24}$ kg; Radius of earth = $6.4 \times 10^{3}$ km; G = $6.7 \times 10^{- 11} N m^{2} / k g^{2}$ )
1. 9.8 newtons
2. 10 newtons
3. 9.8 kg
4. 9.8 newton meter
Calculate the value of acceleration due to gravity on the surface of the moon.(Given mass of the moon = $7.4 \times 10^{22}$ kg, Radius of themoon = 1740 km, G = $6.7 \times 10^{- 11} N m^{2} / k g^{2}$ )
1. $- 1.63 m / s^{2}$
2. 1.63 m/s
3. $1.63 m / s^{2}$
4. $9.8 m / s^{2}$
To estimate a hieght of a bridge over a river, a stone is dropped freely in the river from the bridge. The stone takes 2 seconds to touch the water surface in the river. Calculate the height of the bridge from the water level. (g = $9.8 m / s^{2}$ )
1. 39.2 m
2. 20 m
3. 9.8 m
4. 19.6 m
The force of attraction between two unit point masses separated by a unit distance is called:
1. Gravitational
2. Acceleration due to gravity
3. Gravitational field strength
4. None of these
The wieght of an object on earth is about how much of its weight on moon?
1. 6 times
2. 5 times
3. 7 times
4. 8 times

Laws Of Motion

Quiz