which of these statement is not true?
  • Momentum is product of mass and velocity
  • If a net force acts on the systems,it momentum will change
  • A heavy object will always have higher momentum than lighter object
  • Impulse is the product of Force and time applied
An open truck rolls along a friction-less track while it is raining. As it rolls, what happens to the speed of the truck as the rain collects in it? (assume that the rain falls vertically into the box) ?
  • it increase
  • it decrease
  • remains same
  • Insufficient information
Which of these is false?
  • Momentum is conserved in elastic collision only not in inelastic collision
  • When net force on the system is zero, Total momentum of the system remains conserved
  • When two objects collides and completely bounce back with no deformation and no generation of heat,the collision is said to be elastic
  • None of the above
A bomb that is stationary sitting at the origin on the xyz plane explodes into pieces of different sizes and shapes. ?
  • After the explosion the momentum of all the pieces, exhaust and smoke add up to zero
  • After the explosion the momentum of all the pieces, exhaust and smoke add up to non zero
  • Total momentum is increased an energy is released by the explosion
  • none of the above
Momentum of the objects tells us about?
  • object mass
  • object velocity
  • how difficult it to stop it
  • object weight
A 5 g rubber ball and a 5 g clay ball are thrown at a wall with equal speeds. The rubber ball bounces, the clay ball sticks. Which ball exerts a larger impulse on the wall?
  • They exert equal impulses because they have equal momenta
  • The clay ball exerts a larger impulse because it sticks
  • The rubber ball exerts a larger impulse because it bounces.
  • Neither exerts an impulse on the wall because the wall doesn't move
Which one of the following equations is not dimensionally correct? Following things are given v => is a speed (L/T) a => is an acceleration (L/T2) x => is a distance (L) t => is a time (T) M => is a Mass (M) F => is a force (ML/T2) p => is a momentum ( ML/T)
  • p1i+p2i=p1f+p2f
  • $F=\frac {d(mv)}{dt}$
  • $m(dv)+v(dm)=F$
  • none of these
A small car had a head-on collision with bigger truck. The impulse exerted by the truck on car
  • is less than impulse exerted by car on truck
  • is equal to impulse exerted by car on truck
  • is greater to impulse exerted by car on truck
  • Insufficient information
Two boxes P and Q, having mass m1 and m2 ( m1 > m2) are initially at rest on a horizontal friction-less surface. The same constant force F acts on each one for exactly 5 second. Which box has more momentum after the force acts ??
  • P
  • Q
  • Both have same momentum
  • insufficient information
Robert (120 kg) and Bill (60 kg) are standing on slippery ice and push off each other. If Bill slides at 6 m/s, what speed does Robert have have?
  • 12 m/s
  • 6 m/s
  • 8 m/s
  • 3 m/s
0 h : 0 m : 1 s