Homework Help: physics

Posted by teamjakeward on Wednesday, February 11, 2009 at 8:30pm.

please show me how to do this in steps.

A track star in the long jump goes into the jump at 12 m/s and launches herself at 20.0degrees above the horizontal. What is the magnitude of her horizontal displacement?
(assume no air resistance and that
Ay= -g = -9.81 m/s^2)

thanks :)

physics - drwls, Wednesday, February 11, 2009 at 8:52pm
Her vertical component of velocity at takeoff is
Vyo = 12 sin 20 = 4.10 m/s
and her horizontal component is
Vx = 12 cos 20 = 11.28 m/s.
The horizontal component remains constant during the jump.
Use the vertical velocity component to determine how long she is in the air before hitting the ground. Call that time T

Vo = g T/2
T = 2 Vo^2/g

The length of the jump is Vx*T
= 2 (Vo^2/g) sin 20 cos 20
= (Vo^2/g) sin 40

Answer this Question

Related Questions

Physics - A track star in the long jump goes into the jump at 12 m/s and ...
Physics - A trackstar in the long jump goes into the jump at 12 meters per ...
physics - please tell me if these are correct A track star in the long jump goes...
physics - A track star goes in the long jump at 10 m/s at 37 degrees above the ...
physics - A girl makes a jump in the long jump with an initial velocity of 12 m/...
physics - A girl makes a jump in the long jump with an initial velocity of 12 m/...
Physics - A jumper in the long-jump goes into the jump with a speed of 10m/s at ...
Physics - A jumper in the long-jump goes into the jump with a speed of 10m/s at ...
science - A ski jumper launches from a ski jump that is oriented parallel to a ...
Physics - An athlete competing in long jump leaves the ground with a speed of 9....

For Further Reading

First Name:
School Subject:
Answer: