What is the initial potential energy in the spring?

AI Thread Summary
The discussion focuses on calculating the initial potential energy stored in a spring that propels a wooden block up an incline. The block, with a mass of 1.75 kg, is released from a compressed spring and travels 4.55 meters up a slope inclined at 34 degrees, reaching a speed of 5.85 m/s. Participants emphasize the importance of incorporating kinetic energy, gravitational potential energy, and friction into the calculations, with specific equations provided for each energy type. The height 'h' that the block reaches is determined using trigonometric functions, specifically as 4.55 sin(34 degrees). Understanding these relationships is crucial for solving the problem effectively.
azila
Messages
67
Reaction score
0

Homework Statement


A wooden block with mass 1.75 kg is placed against a compressed spring at the bottom of a slope inclined at an angle of 34.0 (point ). When the spring is released, it projects the block up the incline. At point , a distance of 4.55m up the incline from , the block is moving up the incline at a speed of 5.85 m/s and is no longer in contact with the spring. The coefficient of kinetic friction between the block and incline is = 0.55. The mass of the spring is negligible.

What is the initial potential energy in the spring??

Homework Equations


ok, I know that you do kinetic energy + potential energy +friction
K = .5mv^2
U = mgh
U of spring = .5*k*v^2


The Attempt at a Solution



But How do i account for the angles and mu, if some one could show me the equation..I would understand. I have tried everything.. Thanks in advance
 
Physics news on Phys.org
azila said:

Homework Statement


A wooden block with mass 1.75 kg is placed against a compressed spring at the bottom of a slope inclined at an angle of 34.0 (point ). When the spring is released, it projects the block up the incline. At point , a distance of 4.55m up the incline from , the block is moving up the incline at a speed of 5.85 m/s and is no longer in contact with the spring. The coefficient of kinetic friction between the block and incline is = 0.55. The mass of the spring is negligible.

What is the initial potential energy in the spring??

Homework Equations


ok, I know that you do kinetic energy + potential energy +friction
K = .5mv^2
U = mgh
U of spring = .5*k*v^2


The Attempt at a Solution



But How do i account for the angles and mu, if some one could show me the equation..I would understand. I have tried everything.. Thanks in advance
The angle will help you to determine 'h' in the 'mgh' term, and also will aid in determining the value of the normal force used in your calcuation of the friction force.
 
how would i calculate h though? i don't know?? please help
 
would h just be mgmucostheta
 
azila said:
would h just be mgmucostheta
No, what's h got to do with mu?
h is the height that the block reaches above ground when it is 4.55m up the incline. From trig, h is just 4.55 sin theta, no?
 
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

Why can we move the spring with constant speed when we apply a force?
Replies
29
Views
2K
Distribution of Energy when work is done on a system of 2 masses connected by a spring
Replies
17
Views
2K
Find elastic energy in the compressed spring.
Replies
12
Views
3K
How can I calculate the potential energy stored in a compressed spring?
Replies
4
Views
2K
Initial velocity of bird landing on horizontal wire modeled as spring
Replies
7
Views
974
A rocket on a spring, related to potential/kinetic energy
Replies
3
Views
2K
Question about springs and rotational/translational energy
Replies
4
Views
1K
Pan suspended by a spring (Energy + SHM)
Replies
20
Views
3K
Problem with when to use Force and Energy. What compresses spring/
Replies
3
Views
1K
Force components for mass attached to two springs
Replies
15
Views
1K

Hot Threads

Recent Insights

Back
Top