Work
The SI unit of work is?
Joules(J)
What is the definition of power in physics?
Amount of work done
What are the two main types of mechanical energy?
kinetic energy - potential energy
What is the formula for efficiency?
Efficiency=(Total Input Energy/Useful Output Energy)×100%
A 1000 kg car is pushed with a force of 200 N at an angle of 30 degrees to the horizontal for a distance of 10 m. How much work is done on the car?
1732 J
A 2 kg ball is drpped from a height of 5 m. What will be its speed just bfore hitting the grond?
9.9m/s
A machine does 5000 J of work in 10 seconds. What is its power output in watts and horsepower?
500W
A motor receives 2000 J of electrical energy and converts it into 1500 J of useful mechanical work. What is its efficiency?
75%