High Jumper Acceleration Calculation

  • Thread starter Thread starter vickic
  • Start date Start date
  • Tags Tags
    Physics
AI Thread Summary
To calculate the horizontal and vertical acceleration of a 76kg high jumper experiencing a ground reaction force (GRF) of 1750N at a 70-degree angle, one must first resolve the GRF into its x (horizontal) and y (vertical) components using trigonometry. The horizontal component is found by multiplying the GRF by the cosine of the angle, while the vertical component is determined by multiplying the GRF by the sine of the angle. After calculating the net forces in both directions, apply Newton's second law (net force = mass * acceleration) to find the respective accelerations. The jumper's vertical acceleration must also account for the downward force of gravity, which is 9.81 m/s². Understanding these calculations is crucial for determining the jumper's performance during takeoff.
vickic
Messages
2
Reaction score
0
Hi, I am really stuck on this question, any help would be really really helpful!

During takeoff a 76kg high jumper experiences a GRF of 1750N acting at an angle of 70 degrees to the horizontal. Taking acceleration due to gravity to be 9.81 ms and ignoring air resistance, calculate the HORIZONTAL and VERTICAL accleration experienced by the jumper at this point in time.

I think i need to work out the net force first, but after this I am completely confused. Thanks :frown:
 
Physics news on Phys.org
1. calc net force in x- and y composants

2. Net force = mass * acceleration, Newtons famous law.
 
i understand the equation and got the net force to be 745.6 ? but i dnt understand how to fo it for x (horizontal) and Y (vertical). I know this probs sounds daft but physics really isn't my strong point! Thanku
 
in what direction?...

and what is GRF ?
 
and yeah, use trigonometry.
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Thread 'Struggle to understand the concept of the question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »

Similar threads

Average Net force and high jumpers
Replies
27
Views
4K
How high can a high jumper clear on the moon compared to on Earth?
Replies
4
Views
2K
Calculating the weight when faced with multiple accelerations
Replies
20
Views
2K
Calculate initial speed of an athlete - projectile motion
Replies
15
Views
3K
Calculating Take-Off Velocity for High Jumper Kwaku Boateng
Replies
2
Views
2K
How High Does a Jumper Raise Their Center of Gravity?
Replies
3
Views
2K
Minimum force to tip the bin over
Replies
7
Views
967
How to calculate the horizontal shift?
Replies
3
Views
1K
Finding the Average Acceleration
Replies
12
Views
2K
Having a hard time learning Newton's 2nd law
Replies
5
Views
2K

Hot Threads

Recent Insights

Back
Top