Mechanics | Relativity Answers

The gravitational force on a baseball is -Fgj. A pitcher throws the baseball with velocity vi by uniformly accelerating it straight forward horizontally for a time interval Δt = t − 0 = t. If the ball starts from rest, determine the following: (Use any variable or symbol stated above along with the following as necessary: g for the acceleration due to gravity.)

During a storm, a crate of crepe is sliding across a slick, oily parking lot through a displacement d=(-3.0m)i while a steady wind pushes against the crate with a force F=(2.0N)i+(-6.0N)j. (a) How much work does this force do on the crate during the displacement? (b) If the crate has a kinetic energy of 10J at the beginning of displacement d, what is its kinetic energy at the end of d?

A garage mechanic uses a stroboscope to equilibrate a wheel. By decreasing the frequency of flashes, he observes that the wheel appears stationary for frequencies 60 Hz, 30 Hz, 20 Hz,... Calculate the frequency of the wheel.

A projectile is launched at ground level with an initial speed of 50.0 m/s and an
elevation angle (i.e., at an angle above the horizontal) of 30.0°. It strikes a target above the
ground 3.00 s later. What are the horizontal and vertical distances of the target from the place
where the projectile was launched? Ignore air resistance.

A football is kicked at ground level in such a way that its initial horizontal speed is
12 m/s and its initial vertical speed is 17 m/s. Assume a level playing field and ignore air
resistance. (a) How much later does the football hit the ground? (b) How far away does it land?

The top of the pool table is 2.75 ft from the floor. The placement of the tape is such that 0 feet aligns to the edge of the table (as shown). The winner of the competition wants to know if he has broken the world record for the break shot of 32 mph. His ball landed a distance 15.75 ft from the table edge. Calculate his break shot speed.

An automobile and a truck start from rest at the same instant, with the automobile initially at some distance behind the truck. The truck has a constant acceleration of 2 m/s and the automobile an acceleration of 3 m/s. The automobile overtakes the truck after the truck has moved 75 cm. How long does it take the auto to overtake the truck? How far was the automobile behind the truck initially? What is the velocity of each when they are abreast?

a water tank is on the roof of a hose. a faucet is opened on the ground floor 140 ft below the water level in the tank .with what velocity will water emerge from the faucet

While curling, you push a rock for 1.70 m and release it when it has a speed of 1.70 m/s. It continues to slide at constant speed for 0.700 s and then hits a rough patch of ice. It finally comes to rest 9.20 m from where it was released.

What was the curling rock's magnitude of acceleration after it hit the patch of rough ice?

A ball thrown vertically up from ground level with an initial velocity of 5 m/s. What is the maximum height it attains?