Question

A bus and a car have the same momentum If the kinetic energy of bus is K1 and that of the car is K2, then:

• A. K 1=K2
• B. K 1<K2
• C. K 1>K2
• D. K 1>= K2

Answer 1

Answer:

B. K 1<K2

• Momentum (p): Defined as the product of an object's mass (m) and its velocity (v). Mathematically, p = mv. Momentum is a vector quantity, possessing both magnitude and direction.

• Kinetic Energy (K): The energy possessed by an object due to its motion. Mathematically, K = 1/2 mv2. Kinetic energy is a scalar quantity.

Relating Momentum and Kinetic Energy

We can express kinetic energy in terms of momentum:

• From p = mv, we get v = p/m.

• Substitute this into the kinetic energy formula: K = 1/2 m (p/m)2 = 1/2 m (p2/m2) = p2 / (2m).

• Therefore, K = p2 / (2m).