Question

In: Physics

A ball is thrown horizontally off the edge of a cliff with an initial speed of...

A ball is thrown horizontally off the edge of a cliff with an initial speed of 20 m/s

. how long does it take for the ball to fall to the ground 86.3 m below?

.How long would it take for the ball to reach the ground 86.3 m below if it were dropped from rest off the cliff edge ?

. how long would it take the ball to fall to the ground 86.3 m below if it were thrown at an initial velocity of 20 m/s but 18° below the horizontal?

Expert Solution

The concept behind these types of problems is simple. The motion of any object can be resolved into a horizontal and vertical component. To calculate anything regarding the horizontal/vertical distance or time etc, we can only consider the horizontal/vertical component.

Part 1

The initial vertical component of the velocity is zero. Therefore, the time taken is

Part 2

In this case as well, the initial vertical component of velocity is zero. Therefore, the time taken to reach the bottom is the same as in Part 1.

Part 3

In this case, the initial vertical component is not zero. Since the angle the velocity makes is given with respect to below the horizon, the vertical component is the sine of the angle times the initial velocity.

Since the gravity acts in the same direction as the initial vertical velocity, we get

Putting in our numeric values and rearranging the above equation, we get

Solving this, we get

We actually also get a negative value, which is to be neglected.

genius_generous answered 2 years ago

A ball is kicked horizontally with 15 m/s initial speed from a cliff. The ball lands...

A ball is kicked horizontally with 15 m/s initial speed from a cliff. The ball lands 75 m away from the base of the cliff (R = 75m). What is the height of the cliff? What is the hitting velocity (the velocity of the ball before it hits the ground)? What is the total time of flight?

A ball is thrown toward a cliff of height h with a speed of 27m/s and...

A ball is thrown toward a cliff of height h with a speed of 27m/s and an angle of 60? above horizontal. It lands on the edge of the cliff 3.9slater. Part AHow high is the cliff? Part bWhat was the maximum height of the ball? PartC What is the ball's impact speed?

A projectile is shot from the edge of a cliff at an initial speed of 5.0...

A projectile is shot from the edge of a cliff at an initial speed of 5.0 m/s at angle 30o with the horizontal. After 12 seconds, the projectile hits the ground below at some point P. (a) Determine the height of the cliff above ground level. (b) Determine the distance of the point P from the base of the vertical cliff. (c) At the instant just before the projectile hits point P, find the horizontal and the vertical components of...

A ball is thrown toward a cliff of height h with a speed of 30 m/s...

A ball is thrown toward a cliff of height h with a speed of 30 m/s and an angle of 60° above horizontal. It lands on the edge of the cliff 4.0 s later. How high is the cliff? What was the maximum height of the ball? What is the ball’s impact speed?

An otter jumps horizontally off a cliff with a speed of 2.72 m/s and lands in...

An otter jumps horizontally off a cliff with a speed of 2.72 m/s and lands in the water a horizontal distance of 4.67 m from the edge of the cliff. How high above the water did the otter jumps from? _________ m

A beanbag of mass 185 grams is thrown horizontally with an initial speed of vi =...

A beanbag of mass 185 grams is thrown horizontally with an initial speed of vi = 2.4 m/s from a height 1.2 meters above a level ground. When it reaches the ground, the beanbag comes to a rest in 819 milliseconds. What is the average friction force acting from the ground onto the beanbag during this collision, in units of Newtons? Since you are computing a magnitude of force, your answer should be a positive number.

A ball is thrown straight up with an initial speed of 19 m/s. The ball was...

A ball is thrown straight up with an initial speed of 19 m/s. The ball was released 6.3 m above the ground, but when it returns back down, it falls into a hole d m deep. If the ball’s speed is 35.7 m/s at the bottom of the hole, how deep is the hole (in m)?

•A ball is thrown upward from an initial height of 4.9 m with an initial speed...

•A ball is thrown upward from an initial height of 4.9 m with an initial speed of 9.8 m/s •How high is the ball 2.0 s later? •What is the velocity of the ball at its highest point •When does it reach Its highest point •How high does the ball go? •When does the ball hit the ground? •How fast is it going when (right before) it hits the ground?

A 43.0 g ball is fired horizontally with initial speed v0toward a 107 g ball that...

A 43.0 g ball is fired horizontally with initial speed v0toward a 107 g ball that is hanging motionless from a 1.2 m -long string. The balls undergo a head-on, perfectly elastic collision, after which the 107 g ball swings out to a maximum angle θmax = 50.0 ∘. What was v0?

A woman stands at the edge of a cliff and throws a rock horizontally over the...

A woman stands at the edge of a cliff and throws a rock horizontally over the edge with a speed of v0 = 16.0 m/s. The rock leaves her hand at a height of h = 33.0 m above level ground at the bottom of the cliff, as shown in the figure. Note the coordinate system in the figure, where the origin is at the bottom of the cliff, directly below where the rock leaves the hand. Write the equations...