Which of these is the equation for work done? A work done = force ÷ distance moved in direction of force B work done = force × distance moved in direction of force C work done = force × distance moved at right angles to direction of force D work done = force × distance moved at right angles to direction of force (b) A ball has a mass of 0.046kg - Edexcel - GCSE Physics - Question 2 - 2019 - Paper 1

To find the change in gravitational potential energy (ΔGPE), we use the formula:

$$ΔGPE = m × g × Δh$$

Where:

• m = mass of the ball = 0.046 kg
• g = acceleration due to gravity ≈ 9.81 m/s²
• Δh = height lifted = 2.05 m

Now substituting the values:

$$ΔGPE = 0.046 imes 9.81 imes 2.05 \ ΔGPE = 0.046 imes 20.202 \ ΔGPE ≈ 0.929 ext{ J}$$

Thus, the change in gravitational potential energy is approximately 0.929 J.

To calculate the kinetic energy (KE) of the ball, we use the formula:

KE = rac{1}{2} m v^2

Where:

• m = mass of the ball = 0.046 kg
• v = speed of the ball = 3.5 m/s

Now substituting the values:

KE = rac{1}{2} imes 0.046 imes (3.5)^2 \ KE = 0.023 imes 12.25 \ KE ≈ 0.28175 ext{ J}

Thus, the kinetic energy of the ball is approximately 0.28175 J.