Particle Launched over 13.7m Gorge - Speed & Angle Calculation

  • Thread starter Thread starter 7yler
  • Start date Start date
  • Tags Tags
    Particle
AI Thread Summary
The discussion focuses on calculating the launch speed of a particle projected over a 13.7 m gorge at a 14° angle, landing with 1.7 m to spare. The initial calculation suggested a speed of 16 m/s, but it was pointed out that gravity must be factored into the equation, as it affects projectile motion. The conversation also touches on how launch speed varies based on gravitational forces on different celestial bodies. Additionally, there is a query about determining the launch angle if the particle falls 0.5 m short when launched at a different angle. The participants emphasize the importance of including gravitational acceleration in their calculations for accurate results.
7yler
Messages
31
Reaction score
0
A particle is launched over a gorge that is 13.7 m straight across and 100 m deep. The particle is launched at an angle of 14° above the horizontal, and lands with 1.7 m to spare.
What was the particle's launch speed?
If the particle was launched at a different angle, but fell 0.5m short, what would it's launch angle be?

For the first part, I figured that the launch speed should be x, where x*cos(14 deg) = 15.4 m, so x = 16 m/s, but this is not correct. Why?
 
Physics news on Phys.org
I got a different answer. Your answer is wrong because gravity affects the answer and you have no g in yours. On the moon a smaller speed would suffice, while on Jupiter a very large velocity is needed.

Show your work and someone will be very happy to sort it out!
 
I realized what I was doing wrong. Thanks for the tip.
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
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 hanging 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