Dana is on a train traveling at a speed of 20 km/h. Dana walks from the front of the train to the back of the train at a speed of 4 km/h. What is Dana's speed relative to the ground?

Jenny is sitting on a sled on the side of a hill inclined at 15°. What force is required to keep the sled from sliding down the hill if the combined weight of Jenny and the sled is 90 pounds?

In the manufacturing of computer chips, cylinders of silicon are cut into thin wafers that are 3.00 in. in diameter and have a mass of 1.50 g of silicon. How thick, in millimeters, is each wafer if silicon has a density of?

Why do engineers place tolerances on dimensions?

What is the name given to the syestem of units used in the united states

If an object moves with a constant velocity, what is the acceleration of the object? What is the net force acting on the object?

Which of the following statements are true? Check all that apply. O A positive charge and a negative charge attract each other. O Electric charge is conserved. O Two positive charges attract each other. O A neutral object contains no charge.

You push a shopping cart filled with groceries (total mass = 20 kg) by applying a force to the cart 30° from the horizontal. if the force you apply has a magnitude of 86 n, what is the cart's acceleration? assume negligible friction.

Two objects are made of the same material, but they have different masses and temperatures. If the objects are brought into thermal contact, which one will have the greater temperature change

A ball strikes a wall. It exerts a force of 10 N to the left against the wall and bounces off. What force does the wall exert on the ball?

A car slows down from 24 m/s to rest in a distance of 90 m. what was its acceleration, assumed constant? incorrect: your answer is incorrect. m/s2