Calculate Velocity of 20g Bullet Striking 15kg Mass on Spring

  • Thread starter Thread starter hodgepodge
  • Start date Start date
  • Tags Tags
    Spring
AI Thread Summary
To calculate the velocity of a 20g bullet striking a 15kg mass attached to a spring, the conservation of momentum is key, while energy is only conserved after the bullet embeds in the block. The spring constant is given as k=200 N/m, and the spring compresses by 12 cm. The final energy stored in the spring can be calculated using the formula for spring potential energy, which is essential for determining the initial velocity of the bullet. The initial calculations yield a velocity of approximately 10.89 m/s, but verification of computations is necessary to ensure accuracy. The bullet remains embedded in the block after the collision, impacting the energy transfer dynamics.
hodgepodge
Messages
47
Reaction score
0

Homework Statement


A 20 gram bullet strikes a 15 kg mass attached to a spring. The mass slides and compresses the spring by 12 cm. Calculate the velocity of the bullet initially. (No Friction!)

k=200n/m


bullet mass spring
=D I---------I II
I ICCCCCCCCCII
____I________I__________II

sorry after i posted it i realized how messed up the pic was
 
Last edited:
Physics news on Phys.org
Hint: Momentum is always conservedsecret hint: Energy is not conserved, until after the bullet is embedded in the block.
 
does my answer of 10.88995 m/s seem correct?
 
Not what I got, and it isn't simply off by an order of 10^n it just seems wrong. Check your computations, make sure you used the correct formula for Ke of a spring. and one more hint, work the problem backwards. Find the Energy at the end and work back until the point of the initial block's velocity, and then yaddi yaddi yadda.
 
does the bullet stay in the block?
 

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

Distribution of Energy when work is done on a system of 2 masses connected by a spring
Replies
17
Views
2K
Irodov- 1.123- Simple conceptual question with two masses connected by a spring
Replies
20
Views
636
Question about springs and rotational/translational energy
Replies
4
Views
1K
How High Does Cheese Rise on a Released Spring?
Replies
1
Views
1K
Calculating Spring Constant for a Mass-Spring System: Technician's Experiment
Replies
1
Views
1K
Having trouble on this energy and momentum question
Replies
4
Views
4K
Shm , calculation of amplitude of spring mass system
Replies
3
Views
2K
Bullet hits mass attached to spring with pic
Replies
5
Views
4K
Mass sliding on frictionless inclined plane compresses a spring
Replies
7
Views
3K
Bullet+block+spring physics homework
Replies
7
Views
10K

Hot Threads

Recent Insights

Back
Top