Show:
Freely Falling objects
One-Dimension motion with constant acceleration
Instantaneous Velocity
misc #1
misc #2
100
A ball is thrown vertically upward with a speed of 25.0 m/s. How high does it rise?
What is 31.9 m
100
The minimum distance required to stop a car moving at 35.0 mi/h is 40.0 ft. What is the minimum stopping distance for the same car moving at 70.0 mi/h, assuming the same rate of acceleration starts?
What is 160 ft
100
A person travels by car from one city to another with different constant speeds between pairs of cities. She drives for 30.0 min at 80.0 km/h, 12.0 min at 100 km/h, and 45.0 min at 40.0 km/h, and spends 15.0 min eating lunch and buying gas. Determine the average speed for the trip.
What is 52.9 km/h
100
Yes or No: If the velocity of a particle is nonzero, can its acceleration be zero?
What is Yes
100
Yes or No: Can the instantaneous velocity of an object at an instant of time ever be greater in magnitude than the average velocity over a time interval containing the instant?
What is Yes
200
Killer whales at sea world routinely jump 7.5 m above the water. What is their speed as they leave the water to achieve this?
What is 12 m/s
200
A cessna aircraft has a lift-off speed of 120 km/h. What minimum constant acceleration does this require if the aircraft is to be airborne after a takeoff run of 240 m?
What is 2.32 m/s^2
200
Two boats start together and race across a 60 km wide lake and back. Boat B goes across at 30 km/h and its crew, realizing how far behind it is getting, return s at 90 km/h. Turnaround times are negligible, and the boat that completes the round trip first eins. Which boat wins and by how much?
What is Boat A by 60 km/h
200
A driver in a car traveling at a speed of 60 mi/h sees a deer 100m away on the road. Calculate the minmum constant acceleration that is necessary for the car to stop without hitting the deer (assuming that the deer doesn't move in the meantime).
What is -3.6 m/s^2
200
A truck tractor pulls two trailers, one behind the other, at a constant speed of 100 km/h. It takes 0.600 s for the big rig to completely pass onto a bridge 400 m long. For what duration of time is all or part of the truck-trailer combination on the bridge?
What is 15.0 s
300
A small mailbag is released from a helicopter that is descending steadily at 1.50 m/s. After 2.00 s, what is the speed of the mailbag?
What is 21.1 m/s
300
A train is traveling down a straight track at 20 m/s when the engineer applies the brakes, resulting in an acceleration of -1.0 m/s^2as long as the train is in motion. How far does the train move during a 40 s time interval starting at the instant the brakes are applied?
What is 200 m
300
A motorist drives north for 35.0 minutes at 85.0 km/h and then stops for 15.0 minutes. He then continues north, traveling 130 km in 2.00 h. What is his total displacement?
What is 180 km
300
A drag racer starts her car from rest and acceleration at 10.0 m/s^2 for the entire distance of 400 m(1/4 mile). How long did it take the race car to travel this distance?
What is 8.94 s
300
A ball is a thrown upward from the ground with an initial speed of 25 m/s; at the same instant, a ball is droopped from a building 15m high. After how long will the balls be at the same height
What is 0.60 s
400
A model rocket is launched straight upward with an initial speed of 50.0 m/s. It accelerates with a constant upward acceleration of 2.00 m/s^2 until its engines stop at an altitude of 150 m. What is the maximum heigh reached by the rocket?
What is 308 m
400
A car starts from rest and travels for 5.0 s with a uniform acceleration of +1.5 m/s^2. The driver then applies the brakes, causinga uniform acceleration of -2.0 m/s^2. If the brakes are applied for 3.0 s. How fast is the car going at the end of the braking period?
What is 1.5 m/s
400
A person takes a trip, driving with a constant speed of 89.5 km/h except for a 22.0 min rest stop. If the person's average speed is 77.8 km/h, how much time is spent on the trip and how far does the person travel?
What is 2.80 h, 218 km
400
A certain car is capable of accelerating at a rate of +0.60 m/s^2. How long does it take for this car to go from a speed of 55 mi/h to a speed of 60 mi/h?
What is 3.7 s
400
A person sees a lightning bolt pass close to an airplane that is flying in the distance. The person hears thunder 5.0 s after seeing the bolt, and sees the airplane overhead 10 s after hearing the thunder. The speed of soundin air is 1100 ft/s. Find the distance of the airplane from the person at the instant pf the bolt (neglect the time it takes the light to travel from bolt to the eye).
What is 5.5E^3 ft
500
A student throws a set of keys vertiically upward to her sorority sister, who is in a window 4.00 m above. the keys are caught 1.50 s later by the sister's outstretched hand. With what initial velocity were the keys thrown?
What is 10.0 m/s upwards
500
A hockey player is standing on his skates on a frozen pond when an opposing player, moving with a uniform speed of 12 m/s, skates by withh the puck. After 3.0 s, the first player makes up his mind to chase his opponent. If he accelerates uniformly at 4.0 m/s^2, how long does it take him to catch his opponent?
What is 8.2 s
500
In order to qualify for the finals in a racing event, a race car must achieve an average speed of 250 km/h on a track with a total length of 1600 m. If a particular car covers the first half of the track at an average speed of 230 km/h, what minimum average speed must it have in the second half of the event in order to qualify?
What 274 km/h
500
A particle is moving with a velocity of 60.0 m/s in the positive x direction at t=0. Between t=0 and t=15.0s the velocity decreases uniformly to zero. What was the acceleration during 15s interval?
What is -4.0 m/s^2
500
A stunt women sitting ona tree limb wishes to drop verically onto a horse galloping under the tree. The constant speed of the horse is 10.0 m/s, and the women is initially 3.00 m above the level of the saddle. What must be the horizontal distance between the saddle and limb when the women makes her move?
What is 7.82 m