In speed skating, the ice skates have toe picks at the end of each blade. This allows the athlete to push off from the ice with a high initial force when the race starts. These toe picks produce what type of force?

A12-kg bag of groceries is tossed onto a table at 4.0 m/s and slides to a stop in 2.2 s . modify the equation fδt=δ (mv) to find the force of friction.

Awind turbine is initially spinning at a constant angular speed. as the wind's strength gradually increases, the turbine experiences a constant angular acceleration 0.173 rad/s2. after making 2870 revolutions, its angular speed is 132 rad/s. (a) what is the initial angular velocity of the turbine? (b) how much time elapses while the turbine is speeding up?

Agas expands from an initial volume of 0.040 m^3 and an initial pressure of 210 kpa to a final volume of 0.065 m^3 while its temperature is kept constant. how much work is done by the system?