Given I climb two steps every second and I have a mass of 50kg, what is the power output of my legs in kilowatts? (3 significant figures)
(There is a diagram showing stairs with steps that are 20cm high)
Power = Energy/TimeEnergy required to climb one step = Work Done = ForceDistanceForce = Weight = mg = 509.81 = 490.5NEnergy = 490.50.2 = 98.1JPower = 98.1/0.5 = 196.2W = 0.196kW (3.s.f)
TG
Related Physics GCSE answers
All answers ▸Why is the car moving if the unbalanced force is zero?
A jug containing 0.250 kg of liquid is put into a refrigerator. Its temperature decreased from 20°C to 15°C. The amount of energy transferred from the liquid was 5,250 J. Calculate the specific heat capacity of the liquid.
A coil is connected to a voltmeter. A bar magnet, initially held above the coil, is left to fall into the coil. Explain why the voltmeter shows a reading. How will the reading of the voltmeter be affected if the magnet is dropped from a greater height?
A bat emits a sound wave with a frequency of 25.0 kHz and a wavelength of 0.0136 metres. Calculate the speed of this sound wave.