Physical World 1 - 11.30am

Formulas for Test 2

Speed or velocity = change in distance/change in time, v = d/t [Units: m/s]

Acceleration = change in velocity/change in time, a= (v_f - v_i)/t [Units: m/s/s or m/s²]

For acceleration under gravity (starting from rest at time t = 0s)

v = gt

d = 0.5gt²

Newton's second law of motion

Net force, F_net = ma [Units: N]

Weight, W = mg [Units: N]

Momentum, p = mv [Units: kg m/s]

Impulse = F_nett = change in momentum = p_f - p_i

Kinetic energy, KE = 0.5mv² [Units: J]

Gravitational potential energy, GPE = mgh [Units: J]

Work, W = Fd [Units: J]

Gravitational force, F = GMm/r² [Units: N]

Acceleration due to gravity at the surface of a planet, g = GM/r²