A 0.80 kg trolley is released from rest at the top of a frictionless ramp, 1.0 m above the bottom. What is its speed at the bottom? (g = 9.8 N/kg)
Answer and explanation
Correct answer: D. 4.4 m/s
- Step 1: Ep lost = Ek gained: mgh = ½mv², so the mass cancels.
- Step 2: v² = 2gh = 2 × 9.8 × 1.0 = 19.6.
- Step 3: v = √19.6 ≈ 4.4 m/s.
Answer
4.4 m/s.
Why not the others: 19.6 m/s: this is v², not v. 9.8 m/s: this is the gravitational field strength. 3.1 m/s: the factor 2 was missed (v² = gh).
Practise more Properties of Matter, Waves and Radiation.
Free questions with an explanation for every one, and full timed National 5 (Scotland) mock tests.
More Properties of Matter, Waves and Radiation questions
- A force of 600 N is applied to an area of 0.020 m². What is the pressure?
- Calculate the energy needed to raise the temperature of 2.0 kg of water by 10 °C (c = 4180 J/kg/°C).
- How much energy is needed to melt 0.50 kg of ice at 0 °C? (specific latent heat of fusion of ice = 3.34 × 10⁵ J/kg)
- A gas at a constant temperature has a volume of 4.0 litres at 100 kPa. It is compressed to 2.0 litres. What is the new pressure?
- A sealed container of gas at 300 K and 100 kPa is heated at constant volume to 360 K. What is the new pressure?
- What is 20 °C in kelvin?