Physics Problems: Seeking Help to Get Started

AI Thread Summary
Help is requested for solving several physics problems involving circular motion, energy transfer, and power calculations. The first problem involves determining the maximum height a grappling hook can reach when whirled in a vertical circle at three revolutions per second. The second problem requires calculating the hammer's speed needed to send a metal piece upward to ring a bell, considering energy loss. The third problem focuses on finding the power needed to maintain a motorcycle's speed against air resistance on both level and inclined roads. Clarification on concepts like speed, kinetic energy, and power is also sought.
Meiersux
Messages
1
Reaction score
0
I would like to inquire the help with a few physics problems : THERES NO WORK BECAUSE I HAVE NO CLUE WHERE TO START. SOMEONE TELL ME WHERE TO BEGIN PLEASE. :

1. A grappling hook, attached to a 1.5m-rope, is whirled in a circle that lies in the vertical plane. The lowers point on this circle is at the ground level. The hook is whirled at a constant rate of three revolutions per second. In the absence of air resistance, to what maximum height can the be cast?

2. At a carnival, you can try to ring a bell by striking a target with a 9.00-kg hammer. in response, a 0.400-kg metal piece is sent upward toward the bell, which is 5.00m above. Suppose that 25.0% of the hammer's kinetic energy is used to do the work of sending the metal piece upward. How fast must the hammer be moving when it strikes the target so that the bell just barely rings?


3. A motorcycle (mass of cycle plus rider = 250kg) is traveling at a steady speed of 20.0 m/s. The force of air resistance acting on the cycle and rider is 200N. Find the power necesary to sustain this speed if (a) the road is level and (b) the road is sloped upward at 37 degrees with respect to the horizontal.
 
Last edited:
Physics news on Phys.org
1. can you find the speed that the hook is moving while it is being whirled?
2. how much kinetic energy does it take to move the piece high enough to hit the bell?
3. what is the definition of power?
 

Thread 'Struggling to understand the concept of this 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 »
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 »

Similar threads

Work and Energy of carnival dinner
Replies
2
Views
2K
How Fast Must the Hammer Move to Ring the Bell at the Carnival?
Replies
11
Views
5K
How Can I Solve My Son's Physics Homework Problems?
Replies
1
Views
4K
Can You Solve These College Physics Problems on Energy and Momentum?
Replies
14
Views
11K

Hot Threads

Recent Insights

Back
Top