A small rock is thrown vertically upward with a speed of 25.0 m/s from the edge of the roof of a 21.0-m-tall building. The rock doesn't hit the building on its way back down and lands in the street below. Ignore air resistance.

A pebble rolls off the roof of Science Hall and falls vertically. Just before it reaches the ground, the pebble's speed is 17 m/s. Neglect air resistance and determine the height of Science Hall.

A projectile of mass m = 1.20 kg is fired straight up in the air with an intial speed of 40 m/s What is the maximum height that the bullet reaches? How fast is the projectile going when it is 25 meters off the ground?

A 0.54-kg ball is thrown vertically upward with an initial speed of 14.0 m/s. What is the speed of the ball when it hastravelled three-quarters of the distance to its maximum height?

When you throw a pebble straight up with initial speed 5.0-m/s, it reaches a maximum height H with no air resistance. At what speed should you throw it straight up so it will go 1.7-times as high? Provide your final answer in m/s.

At the base of a frictionless icy hill that rises at 25.0∘ above the horizontal, a toboggan has a speed of 12.1 m/s toward the hill. How high vertically above the base will it go before stopping?

Basidiomycete fungi ballistically eject millions of spores into the air by releasing the surface tension energy of a water droplet condensing on the spore. The spores are ejected with typical speeds of 1.29 m/s, allowing them to clear the "boundary layer" of still air near the ground to be carried away and dispersed by winds. If a given spore is accelerated from rest to 1.29 m/s in 7.10 µs, what is the magnitude of the constant acceleration of the spore (in m/s?) while (a) being ejected? m/s2 (b) Find the maximum height of the spore (in cm) if it is ejected vertically. Ignore air resistance and assume that the spore is ejected at ground level. cm Find the maximum horizontal range of the spore (in cm) if it is ejected at an angle to the ground. Ignore air resistance and assume that the spore (c) is ejected at ground level. cm

Eliza tossed a log at an initial velocity of 10 m/s, at 30º from 1 m off the ground. She did not see the branch hanging 3 m above the ground over top of her. What is the max height of the log to see if hit the branch?

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Falls resulting in hip fractures are a major cause of injury and even death to the elderly. Typically, the hip's speed at impact is about 2.0m/s. If this can be reduced to 1.3 m/s or less, the hip will usually not fracture. One way to do this is by wearing elastic hip pads. A) if a typical pad is 5.0 cm thick and compresses by 2.0 cm during the impact of a fall, what constant acceleration (in m/s^2 and in g's) does the hip under go to reduce its speed from 2.0 m/s to 1.3 m/s? The acceleration that you found in part "a" may seem very large, but to fully understand its effects on the hip, calculate how long it lasts.