Question

Two objects of same material are travelling near you. Object A is a 1.9 kg mass traveling 8 m/s; object B is a 2 kg mass traveling 5 m/s. Which object would make you feel worse if you are hit by it?
1. B
2. the same
3. Unable to determine
4. A

Answer 1

To determine the object which could give the greatest impact we will apply the concept of momentum. The object that has the highest momentum will be the object that will impact the strongest. Our values are

Mass of Object A

$m_A=1.9 kg$

Velocity of object A

$v_A=8ms$

Mass of object B

$m_B=2 kg$

Velocity of object B

$v_B=5ms$

The general formula for momentum is the product between mass and velocity, then

$p = mv$

For each object we have then,

$p_A=m_Av_A=1.9 kg(8ms)=15.2kg \cdot m/s$

$p_B=m_Bv_B=2 kg(5ms)=10kg \cdot m/s$

Since the momentum of object A is greater than that of object B, then object A will make you feel force upon impact.