Question 1

What is the formula for kinetic energy?

Accepted Answer

Kinetic energy is KE = ½ × m × v², where m is mass in kilograms and v is velocity in meters per second. The result is in Joules (J). For example, a 2 kg object moving at 10 m/s has KE = ½ × 2 × 100 = 100 J.

Question 2

What is a Joule?

Accepted Answer

One Joule is the kinetic energy of a 2 kg object moving at 1 m/s. 1 J = 1 kg·m²/s². Common conversions: 1 kJ = 1000 J, 1 calorie = 4.184 J, 1 foot-pound = 1.356 J.

Question 3

What is the difference between kinetic and potential energy?

Accepted Answer

Kinetic energy is the energy of motion (KE = ½mv²). Potential energy is stored energy due to position or state (e.g., gravitational PE = mgh). The total mechanical energy is the sum of both.

Question 4

Why does velocity have a bigger effect than mass on kinetic energy?

Accepted Answer

In the formula KE = ½mv², velocity is squared while mass is linear. Doubling the mass doubles the kinetic energy, but doubling the velocity quadruples it (2² = 4). This is why high-speed impacts are so destructive.

⚡ Kinetic Energy