Which of the following is the best example of kinetic energy? A. A bowling ball rolling toward the pins B. A horse standing in an open field C. A pitcher preparing to throw a ball D. A runner in position at the start line

If you push on a crate with a horizontal force of 100 n and it slides at constant velocity, what is the magnitude and direction of the frictional force acting on the crate?

A small boat is moving at a velocity of 3.35m/s when it is accelerated by a river current perpendicular to the initial direction of motion. The current accelerates the boat at 0.750m/s^2.

Objects that have no mass

A car covers 72 kilometers in the first hour of its journey. In the next hour, it covers 90 kilometers. What is the amount of work done by the car? The total mass of the car, including its passengers, is 2.5 * 103 kilograms. A. 2.8 * 105 joules B. 4.

Which is the best example of increasing entropy? A pile of library books is placed in a neat stack on a shelf. A cyclist pedals harder while riding uphill. A deserted field becomes overgrown with weeds. A dining room is cleaned to remove dust.

Kim holds a pinwheel in the air and says it can be used to model a source of energy. Identify the type of energy Kim's pinwheel models. Explain the type of energy source used.

An example of a stable system

What causes chemical weathering? a. damage caused by animals and plants c. natural acids b. ice wedging d. physical factors

1. Strzała o masie 20 g tuż po wystrzale ma prędkość 50 m/s. Oblicz pracę wykonaną przez zawodniczkę. Ile wynosi energia potencjalna sprężystości napiętej cięciwy? 2. Na trampolinę o współczynniku sprężystości k=2 kN/m stanął zawodnik o masie 80 kg.

Two small plastic spheres between them has magnitude 0.22 N. What is the charge on each sphere is one the other? Explain whether it can be determined from the information give, whether the charges are positive or negative.