Mechanics | Relativity Answers

a car at rest is acted upon by a constant force acquiring a velocity of 22 m/s after 4 s . determine the magnitude of constant force if the car weights 10,800 N

Sally travels by car from one city to another. She drives for 30.0 min at 80 km/h, 12 min at 105 km/h, and 45 min at 40 km/h. She spends 21.0 min eating lunch and buying gas.

(a) Determine the average speed for the trip.
(b) Determine the total distance traveled.

A bird flies in the east direction with a speed of 5 ms−1. The wind is blowing towards north at a
speed of 3 ms−1. Determine the relative velocity of the bird with respect to the wind. Draw
appropriate diagram for solving the problem.

While driving home from school you travel at 95 km/h for 130 km then slow to 65 km/h. You get home in 3 hours and 20 min. How far is your hometown from school and what is the average speed?

A truck on a straight road starts from rest and accelerates at 2.0 m/s2 until it reaches a speed of 20 m/s. Then the truck travels for 20 s at a constant speed until the brakes are applied, stopping the car in a uniform manner in an additional 5.0 s. How long is the truck in motion and what is its average velocity during the motion?

Two stones are thrown simultaneously, one straight upward from the base of a cliff and the other straight downward from the top of the cliff. The height of the cliff is 6.63 m. The stones are thrown with the same speed of 8.97 m/s. Find the location (above the base of the cliff) of the point where the stones cross paths.

The leader of a bicycle race is traveling with a constant velocity of +11.5 m/s and is 12.0 m ahead of the second-place cyclist. The second-place cyclist has a velocity of +9.10 m/s and an acceleration of +1.20 m/s2. How much time elapses before he catches the leader?

The problem goes like this: If you throw an object upward, and you know that it reaches 50% of it's maximum height after 2s, what is the maximum height.

So we know: Acceleration : -9.8m/s^2
and time:2s = 0.5y

I can't figure out how to solve this

Use the 5-step method and be sure to include units where appropriate. Round your answers to the correct number of significant digits.
Adjust the density formula and solve the problems below:

Pure gold has a density of 119.32 g/cm3. How large would a piece of gold be if it had a mass of 3118.97 g?

is there any electrically operating reciprocating tool