Recent content by AZhang

Oh, I get it. Thanks :)

Well, from our energy conservation equation, P(i) + K(i) + W = P(f) + K(f) + Thermal Energy In this case, there is no initial kinetic energy or final potential energy, so our equation would be P(i) + W = K(f) + Thermal Energy, work being the friction force. But then there are two unknowns, both...

A 40 kg child climbs a 2.5 m vertical ladder to the top of a playground slide. Starting from rest at the top of the ladder, the child slides down the incline, which makes an angle of 22 degrees with the horizontal ground. Friction is present during the descent and the child reaches the bottom of...

I do, it's both Work/Time and Total Energy/Time, but I don't know how to use them in this scenario.

A 3400 KG truck is driving up a road inclined at 8 degrees above the horizontal. If the resistive forces such as air drag and friction that act on the car add up to 1200 N, determine the power output necessary to keep the velocity constant at 20 m/s. I don't really get how to set up my...

I'm a little confused. Could you elaborate?

A 2kg block is attached to an ideal spring (for which k = 200 N/m) and is initially at rest on a horizontal frictionless surface. A 100 gram ball of clay is thrown at the block. The clay is moving horizontally with speed V when it hits and sticks to the block. As a result, the pring is...

But if you are adding one, wouldn't there be equilibrium?

So you are adding a force to the floor?

Well, I guess my main question would be: If a normal force is the force the surface exerts in reaction to the forces exerted on it, then how will there ever be anything that is not at equilibrium? Because won't the normal force always equal the forces exerted on the surface?

But I thought the normal force is the force the surface exerts on the object. So if the normal force is increasing when you're pushing down, then wouldn't there be some kind of force making it increase?

But how does the normal force increase?

Ok, so I'm trying to understand the forces involved in jumping, more specifically, right before a person takes off (as in the part where they press into the ground). I know that the weight force is pushing the person down and that the normal force is bigger than the weight force to create a net...