When placed at a certain point, a 4.20 C charge feels an electric force of 2.55 N. What is the magnitude of the electric field at that point?
(Remember, magnitudes are always positive.) (Unit = N/C)

5g of ammonium nitrate was dissolved in 60g of water in an insulated container. the temperature at the start of the reaction was 23.0°c and at the end it was 19.0°c. calculate the energy absorbed by the reaction.

What object a collides with object b and bounces back its final momentum is?

Asmall grinding wheel has a moment of inertia of 4.0×10−5 kg⋅m2 . what net torque must be applied to the wheel for its angular acceleration to be 150 rad/s2 ?