Question

Computer the power output in watt of a machine that lift a 50kg crete through a height of 20cm in 1minute

Answer 1

I will assume this is on Earth, with an acceleration due to gravity of 9.8 m/s/s. Force = mass * acceleration. A 50 kg mass therefore weighs 50 * 9.8 = 490 Newtons, which is the force required to lift the object. The energy required is force times distance, or 490 * 0.2 meters = 98 Joules. (All in the MKS system.) This energy was produced in a time interval of 60 seconds. Power = energy / time. So the power is 98 Joules / 60 seconds = 1.6333 Watts. (One Watt is defined as one Joule per second.)

Answer 2

Answer
ss 2