Question

A rock is dropped from a bridge and it hits the river 4.5s later. How high is the bridge?​

Answer 1

To determine the height of the bridge, we can use the equation of motion for a falling object. The equation is:

h = (1/2)gt^2

Where: - h is the height of the bridge - g is the acceleration due to gravity (approximately 9.8 m/s^2) - t is the time it takes for the rock to fall

Given that the rock hits the river 4.5 seconds later, we can substitute this value into the equation and solve for h:

h = (1/2)(9.8)(4.5)^2

Calculating this, we find that the height of the bridge is approximately 99.225 meters.

Please note that this calculation assumes no air resistance and that the rock is dropped vertically from the bridge.