A motorcyclics performing a stunt - How long is he in the air?

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The discussion focuses on calculating the time a motorcyclist will be in the air while attempting to jump a 25-meter wide river from a cliff that is 20 meters lower on the landing side. To determine the time in the air, the equations of motion are established, incorporating initial speed of 50 m/s and vertical acceleration of -9.8 m/s². The calculations suggest that the motorcyclist would be in the air for approximately 0.5 seconds based on horizontal distance, while another method indicates about 5.1 seconds when considering vertical motion. These calculations are simplified and do not account for factors like air resistance or the angle of the jump. Safety precautions and thorough planning are emphasized as critical for executing such stunts.
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A motorcyclist intends to perform a stunt in which he jumps a 25meter wide river.

The motorcyclist must jump from a cliff on one-side 20 meters lower than the other side.
The motorcyclist approaches the cliff at 50m/s

What formula should I use to solve for

the Horizontal direction?

And the time in the air?
 
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The horizontal direction??

What you want to do is set up the equations for distance covered with unknown angle θ and initial speed 50 m/s. The vertical acceleration is -9.8 m/s2 so the vertical speed at any t is 50 sin(θ)- 9.8t and the vertical height above the starting point is 50 sin(θ)t- 4.9t2. Since the landing side is 20 m higher than the starting side, the jump should end with
50 sin(θ)t- 4.9t2= 20. Also his horizontal distance covered is 50 cos(θ)t. In order to get across the river, he needs to have 50 cos(θ)t= 25. Solve the two equations for t and θ to answer your question.
 


To solve for the horizontal direction, you can use the formula: d = v*t, where d is the distance traveled, v is the initial velocity, and t is the time. In this case, the distance would be 25 meters and the initial velocity would be 50m/s. So, to solve for the time in the air, you would use the formula t = d/v, which would give you a time of 0.5 seconds. This means that the motorcyclist would be in the air for approximately half a second while performing the stunt. However, it's important to note that this is a simplified calculation and there are other factors that could affect the actual time in the air, such as air resistance and the angle of the jump. It's always important to take safety precautions and thoroughly plan and practice stunts like this.
 


To solve for the horizontal direction, you can use the formula: distance = velocity x time. In this case, the distance would be 25 meters and the velocity would be 50m/s. So, the formula would be 25m = 50m/s x time. Solving for time, we get a result of 0.5 seconds in the air for the horizontal direction.

To solve for the time in the air, you can use the formula: time = (final velocity - initial velocity) / acceleration. In this case, the initial velocity is 50m/s and the final velocity would be 0m/s (since the motorcyclist would reach the peak of the jump and then start to descend). The acceleration due to gravity is 9.8m/s^2. So, the formula would be time = (0m/s - 50m/s) / -9.8m/s^2. Solving for time, we get a result of approximately 5.1 seconds in the air.

However, it's important to note that these calculations are based on ideal conditions and do not take into account factors such as wind resistance and the motorcyclist's maneuvering abilities. The actual time in the air may vary. It's always important to prioritize safety and proper training when attempting stunts like this.
 
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