A body of mass 100g moving with a velocity of 10.0ms-1 collides with a wall. If after collision, it moves with a velocity of 2.0ms-1 in the opposite directi...
A body of mass 100g moving with a velocity of 10.0ms-1 collides with a wall. If after collision, it moves with a velocity of 2.0ms-1 in the opposite direction, calculate the change in momentum.
Answer Details
The change in momentum is calculated by subtracting the initial momentum from the final momentum. The momentum of an object is given by the product of its mass and velocity.
Initial momentum = mass × initial velocity
Final momentum = mass × final velocity
The change in momentum is therefore:
change in momentum = final momentum - initial momentum
change in momentum = mass × final velocity - mass × initial velocity
change in momentum = mass × (final velocity - initial velocity)
Substituting the given values:
mass = 100g = 0.1kg
initial velocity = 10.0ms^-1
final velocity = -2.0ms^-1 (since the body moves in the opposite direction)
change in momentum = 0.1kg × (-2.0ms^-1 - 10.0ms^-1)
change in momentum = 0.1kg × (-12.0ms^-1)
change in momentum = -1.2Ns
Therefore, the change in momentum is -1.2Ns. Since momentum is a vector quantity, the negative sign indicates that the direction of momentum has changed, which is in the opposite direction of the initial momentum.