Mechanics | Relativity Answers

n a quarter-mile drag race, two cars start simultaneously from rest, and each accelerates at a constant rate until it either reaches its maximum speed or crosses the finish line. Car A has an acceleration of 11.2 m/s2 and a maximum speed of 105 m/s. Car B has an acceleration of 11.9 m/s2 and a maximum speed of 85.9 m/s. (a) Which car wins the race? Type 1 for A, 2 for B. (b) By how many seconds does this car win the race?

A woman and her dog are out for a morning run to the river, which is located 3.80 km away. The woman runs at 3.65 m/s in a straight line. The dog is unleashed and runs back and forth at 5.33 m/s between his owner and the river, until she reaches the river. What is the total distance run by the dog (in meters)?

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 6.55 m. The stones are thrown with the same speed of 9.42 m/s. Find the location (above the base of the cliff) of the point where the stones cross paths.

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A train has a length of 80.1 m and starts from rest with a constant acceleration at time t = 0 s. At this instant, a car just reaches the end of the train. The car is moving with a constant velocity. At a time t = 13.3 s, the car just reaches the front of the train. Ultimately, however, the train pulls ahead of the car, and at time t = 30.4 s, the car is again at the rear of the train. Find the magnitudes of (a) the car's velocity and (b) the train's acceleration.

A 650kg elevator starts from rest. It moves upward for 3s with constant acceleration and it reaches its cruising speed of 1.75m/s.

1. What is the average power of the elevator motor during this period?
2. How does this power compare with the motor when the elevator moves at its cruising speed?

What is the path difference of two waves having phase difference 60 degrees?

There is a 100kg object on a 30-degree incline ramp.
A motor with a string attached to the object accelerates the object at 0.22 m/s^2
The mew of friction is 0.5. What is the power output of the motor?

there are 2 planes that leaves towards the same city at the same time (15:32pm) one flies at 460km/h and the other flies at 600km/h. how long will it take the faster plane to get 300 km ahead of the slower plane

At an altitude of 2.8 km, a plane is flying horizontally due north at 130 m/s. A ball is dropped out of the window when the plane is directly over the Washington Monument. How long does it take for the ball to hit the ground? And where does it land in respect to the Washington Monument?

The surface of the water in a reservoir is 128 feet above a hydrant. What will the static pressure on the
hydrant created by the head?