How much work is done by a 1000-watt hairdryer in 40 seconds ?

The passing of heat through a material while the material itself stays in place. a. radiation b. conduction c. convection

Crowbar of 5 metre is used to lift an object of 800 metre if the effort arm is 200cm calculate the force applied

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?