If the dolphin is moving horizontally when it goes through the hoop, how high above the water is the center of the hoop?
A dolphin jumps with an initial velocity of 12.0 m/s at an angle of 39.3 above the horizontal. The dolphin passes through the center of a hoop before returning to the water.
The initial velocity is 12.0 m/s with an angle of 39.3 degrees above the horizontal. This means that the initial velocity in the vertical direction is:
Since the dolphin is moving horizontally when it goes through the hoop, it has vertical velocity of 0 at that point. The vertical velocity equation is
`v=-g t + v_y` sub in values
`0=-9.8t+7.6` solve for t
This time can be substituted into the height formula:
`h=-1/2 g t^2+v_y t+h_0` sub in values
The height of the centre of the hoop is 2.94 m above the water.