Question 1:
easyA car accelerates on a horizontal road due to the force exerted by
Friction force applied by road on the car act in the direction of the motion which is responsible to move the car.
Practice NEET Laws of Motion Questions
Question 2:
easyA body of weight W1 is suspended from the ceiling of a room through a chain of weight W2. The ceiling pulls the chain by a force
Total weight of chain + block system is W1 +W2.
Question 3:
easyWhen a constant force is applied to a body, it moves with uniform
From Newton's second law of motion, F= m.a
if force is constant acceleration remains constant.
Question 4:
easyA particle is moving with a constant speed along a straight line path. A force is not required to
As the particle moves with constant speed in straight line its velocity is constant i.e accleration is zero. From Newton's second law of motion
F=m.a
Force required to keep moving with uniform velocity is zero.
Question 5:
easyA passenger in the bus finds that his suit-case suddenly starts sliding backwards. This means that the bus is :
This is due to inertia of motion.Â
Question 6:
easyThe linear momentum of a particle is given by P = a + bt², where t is time and a & b are constants. The force acting on the body is directly proportional to :
Given momentum of the object is P = a + bt²;
Force is defined as rate of change of momentum F= dP/dt= 2bt. so Force is proportional to t.
Question 7:
easyA body of mass 1 kg moving on a smooth horizontal surface with velocity 5m/s is to be brought to rest in 5 sec. How much force need to be applied :
Force is defined as rate of change of momentum ie. F= dP/dt= change in momentum / time
Here Force = (mv-mu)/t= m(v-u)/t= 1 kg (0- 5)/ 5 = 1 N
Question 8:
easyThe momentum of a particle is P = 2cos tˆi + 2sin t ˆj. What is the angle between the force F acting on the particle and the momentum P ?
Momentum of object is given as, P = 2cos tˆi + 2sin t ˆj ,Â
From Newtons Second law, F = dP/dt = -2 sin t î + 2 cos t ˆj.
Taking Dot product of P and F we get = -4 sint . cos t + 4 sint .cost =0 .
So, force and momentum are perpendicular to each other.
Question 9:
easyPassengers standing in a bus are thrown outwards when the bus takes a sudden turn. This happens because of :
Due to inertia of direction person inside the bus has a tendency to move in a straight line. In case of sudden turn body ties to maintain its linear motion.
Question 10:
easyA body moving with uniform velocity is stopped in 0.25 sec by applying a force of 200 N. What is the impulse :
Impulse is change in momentum so, J = F.dt = 200 × 0.25 =50 N-s