Physics in High Jump
Materials: High Jumper
High speed camera
Procedure: Using a high speed camera we took a video of Megan Cremona doing the High Jump. Then, we analyzed the video to determine velocity and acceleration. We also used the logger pro and were able to make some charts and collect data.
d= 1.22 m
t= 0.01 s per frame x 198 frames=1.98 s
weight= 163 lbs
mass= 74.0 kg
= 74.0 kg x 9.8 m/s^2=725.2 N
Vx= 2.04 m/s
Vy= 1.22 m/s
V(using pythag. theorem)= 2.38 m/s
a= 9.8 m/s^2
P=74.0 kg x 2.38 m/s= 207.2 kg m/s
Impulse= 207.2 kg m/s
There is a horizontal motion involved in high jump which carries the jumper across the bar. In the high jump, the kinetic energy of the jumper is transformed into gravitational potential energy. The initial energy is determined by the speed necessary for the forward motion over the bar and the potential energy used to raise the body to the bar.
The graph on the top right shows the position of Megan on the x-axis versus time. The graph on the bottom right shows the position of Megan on the y axis versus time. It has a parabolic shape just as expected. It is like a "throwing stuff" problem.
This graph shows the positions of Megan at each second. With each second, x decreases and y increases.
In conclusion, the video helps to analyze the position of the jumper at each second. By using tracker we werer able to determine the velocity, acceleration, mass and force and momentum/impulse of megan's jump. In order for Megan to achieve maximum height, she must takeoff with the greatest velocity possible. The run-up helps her create a more vertical force, which is enhanced by swinging arms and legs upward before leaving the ground. She must also try to clear the bar with her center of mass as low as possible. She does this by throwing her body horizontally over the bar. This allows her to move thecenter of mass outside her bodies, and the center of mass can then pass under the bar while the body goes over the bar.