How much power does a toaster have if it does 21,000 joules of work in 30 seconds?

Determine the fraction of the magnitude of kinetic energy lost by a neutron (m1 = 1.01 u) when it collides head-on and elastically with a target particle at rest which is 21h (heavy hydrogen, m = 2.01 u).

The pressure proportional to the area a- inversely b- directly c- increase d-decrease

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?