Force Vector Problem: Find Magnitude of Force on Rider from Motorcycle

AI Thread Summary
The discussion revolves around calculating the magnitude of the force on a rider from a motorcycle accelerating up a ramp. The initial approach incorrectly focused solely on the normal force, yielding a result of 646.62 N, which was identified as incorrect. The correct interpretation requires considering both the normal force and the net force due to the motorcycle's acceleration, leading to a net force of 214.4 N. The key realization is that the rider's acceleration indicates additional forces at play beyond just the normal force. Ultimately, the solution involves combining the normal force and the force due to acceleration to find the total force exerted on the rider.
Elmnt
Messages
13
Reaction score
0

Homework Statement


A motorcycle and 67.0 kg rider accelerate at 3.2 m/s2 up a ramp inclined 10° above the horizontal.

What is the magnitude of the force on the rider from the motorcycle?


Homework Equations


I set my 90 degree axis so that my x-axis lined up with the acceleration up the ramp and my y-axis lined up with the normal force. So my y component would be
normal force-mass*gravity*cos 10° = mass*acceleration y


The Attempt at a Solution


I am thinking that the normal force is the force on the rider from the bike and with the way my axis is set up there will be no y acceleration so,

normal force= mass*gravity*cos10°

it gives and answer of 646.62 N but they say this answer is wrong. Am I missing something or misinterpreting?
 
Physics news on Phys.org
Elmnt said:
Am I missing something or misinterpreting?

Well, for some reason you are calculating only the normal force, when this is not what is being asked for.
 
I'm sorry I didn't post the first question asked. Which was:
(a) What is the magnitude of the net force on the rider?

Which I found to be 214.4 N.

I am missing something, What am I supposed to calculate? Isn't normal force the only force from the motorcycle onto the rider? My only other thought is including the acceleration caused by the bike.
 
Elmnt said:
Isn't normal force the only force from the motorcycle onto the rider?

No. If this were the case, why would the rider be accelerating up the ramp?
 
I wasn't paying attention to the force from the motorcycle the accelerates the rider up the ramp. With that now understood I can take the normal force that I had found and use it as a y component and then find the force that the bike applies to the rider going up the ramp and use that as the x component on the rider. Solving for these two components should give me my magnitude of force on the rider from the bike.
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanged mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top