If the velocity of a particle is nonzero, can the particle’s acceleration be zero? Explain.

On a 200 km bike cycle ride, you ride the first 90 km at an average speed of 20 m/s. What mustyour average speed over the next 40 km be to have your average speed for the total 200 km be?(b) Given this average speed for the first 90 km, can you possibly attain an average speed of80 m/s for the total 200 km ride? Explain.

6. A ball is thrown upward with a velocity of 4.5 m/s. Its speed and the magnitude of its acceleration at the highest point (a) are both equal to zero (b) are given by 9.81 m/s and 0 m/s², respectively (c) are given by 0 m/s and 9.81 m/s², respectively (d) cannot be predicted unless the height is known Answer: 7. Which of the following statements about a projectile is not true? Assume that the air resistance is negligible. (a) Its motion is in two dimensions. (b) The only acceleration is in the vertical direction. (c) Its velocity in the horizontal direction remains the same throughout the flight. (d) The velocity at the highest point of its trajectory is zero. Answer:

1st question ?

A projectile is fired from point A at the edge of a cliff, whose initial velocity components are v0x = 60.0m / s and v0y = 175m / s. The projectile rises and then falls into the sea at point P. The projectile flight time is 40.0s and it does not experience appreciable air resistance in flight. a) Make a diagram of the problem, b) Determine how far it falls, c) what is the height of the cliff? and d) at what angle was it shot?

Solve the following problems completely: 1. An athlete jogs north 5.0 km at 4.0 km/h and then west 12 km at 8.0 km/hr. Determine: a) the total distance of the entire trip b) the total displacement of the entire trip c) the average speed of the entire trip d) the average velocity of the entire trip e) the average acceleration of the entire trip 2. A swimmer heads directly across a river swimming at 1.8 m/s relative to still water. She arrives at a point 65 m downstream from the point directly across the river, which is 50 m wide. Determine: a) the speed of the current b) the magnitude of the swimmer's resultant velocity c) the direction of the swimmer's resultant velocity d) the time it takes the swimmer to cross the river

The magnitude of average velocity is always ……to the average speed. equal Less Greater than Less than

You are driving your car uphill along a straight road. Of Suddenly, you see a car go through a red light and enter the intersection, just ahead of you. you. You immediately apply your brakes and skid straight to a stop, leaving a 100 ft long mark from the landslide. A policeman observes the whole incident, give the driver of the car a ticket for running a red light. He also gives a ticket to you for exceeding the 30 mph speed limit. When you get home, you read your physics book and you may notice that the coefficient of kinetic friction between the tires and the road was 0.60, and the coefficient of static friction was 0.80. You estimate that the hill makes an angle of about 10° with the horizontal. Check the manual owner and find that your car weighs 2,050 lbs. Are you going to claim the traffic ticket? in the court? Support your argument.         Please type answer not write by hend

A certain volcano on the Earth can eject rocks vertically to a maximum height H. How high (in terms of H) would these rocks go if a volcano on a planetary object ejected them with the same initial velocity? The accelerations due to the gravity on the Earth and the planetary object are 9.8m/s² and 3.1 m/s?, respectively. Neglect the effect of the air on both planets. 답:

Captain Marvel jumps straight up in the air with a velocity of 30m/s straight up. She reaches a maximum height and then falls back down due to gravity to the same level. This is not a projectile question. a) what max height will she reach? b) How long will it take her to return to the same height from which she jumped c) What will her velocity be when she is just about to hit the ground at the same level she jumped from