A 2 kg metal plate slides down a 14-meter high slope. At the bottom its speed is 11.1 m/s. To the nearest Joule, what was the magnitude of the work done by friction?

To calculate the work done by friction, we first need to find the initial and final potential energy of the metal plate, then calculate the change in kinetic energy. The work done by friction is equal to the change in kinetic energy.

1. Find the initial potential energy (PE₁) of the metal plate using the formula: PE₁ = m * g * h
Where:
- m is the mass of the metal plate (2 kg)
- g is the acceleration due to gravity (9.8 m/s²)
- h is the height of the slope (14 m)

PE₁ = 2 kg * 9.8 m/s² * 14 m = 274.4 J

2. Find the final kinetic energy (KE₂) of the metal plate using the formula: KE₂ = 0.5 * m * v²
Where:
- m is the mass of the metal plate (2 kg)
- v is the final velocity of the plate (11.1 m/s)

KE₂ = 0.5 * 2 kg * (11.1 m/s)² = 123.21 J

3. Find the change in kinetic energy (∆KE) using the formula: ∆KE = KE₂ - KE₁
∆KE = 123.21 J - 0 J = 123.21 J

4. The work done by friction is equal to the change in kinetic energy (∆KE).
Therefore, the magnitude of the work done by friction is approximately 123.21 J.