Physics Homework Problem:Kinematics

AI Thread Summary
A car drives off a 51 m high cliff and lands 134 m from the base, prompting a kinematics problem to determine its speed at the edge. The motion consists of a horizontal velocity with no horizontal forces and a vertical acceleration due to gravity. By applying the kinematic equation Vf^2 = V0^2 + 2ad, where Vf is 0 m/s, the acceleration is 9.8 m/s², and the distance is 51 m, the initial velocity (V0) is calculated to be 31.6 m/s. This speed assumes the car traveled horizontally off the cliff without any vertical component. The solution highlights the importance of understanding the components of motion in projectile dynamics.
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A car drives straight off the edge of a cliff that is 51 m high. The police at the scene of the accident note that the point of impact is 134 m from the base of the cliff. How fast was the car traveling when it went over the cliff?

I don't know where to begin with this problem. Can someone help me out please?
 
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When the car rides off the cliff it will follow a parabolic path.
This is the result of two motions due to two velocity components:
A uniform velocity in the horizontal direction (no force acting horizontally).
A constant acceleration vertically (constant gravitational force acting downwards).

Set up the equations of motions for these directions and use the given data to solve for the speed of the car.
 


Sure, let's break down the problem step by step. We know that the car was on top of a 51 m high cliff and it traveled 134 m before hitting the ground. We also know that the car was not thrown or dropped from the cliff, but rather drove off the edge. This means that we can use the equations of kinematics to solve for the initial velocity of the car.

First, let's define our variables. We know that the initial velocity of the car (V0) is what we are trying to find. The final velocity (Vf) will be 0 m/s since the car comes to a stop when it hits the ground. The acceleration (a) is due to gravity and is equal to 9.8 m/s^2. The distance (d) is 51 m since the car traveled straight down from the top of the cliff.

Now, we can use the equation Vf^2 = V0^2 + 2ad to solve for V0. Plugging in our known values, we get 0^2 = V0^2 + 2(9.8)(51). Solving for V0, we get V0 = 31.6 m/s.

Therefore, the car was traveling at a speed of 31.6 m/s when it went over the cliff. It's important to note that this answer assumes the car was traveling horizontally off the edge of the cliff. If the car had any vertical velocity, the answer would be different. I hope this helps clarify the problem for you.
 
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