A tow truck of mass 2500 kg is pulling a car of mass 1100 kg up an embankment with a motorized winch mounted on its bed, as shown in the figure. The embankment makes an angle of 30 degree with the horizontal. The wheels of the car initially turn freely, so you can neglect the friction between the car and the slope for now.
Answer: 22cm
For the final 8.00 m of the embankment, the ground is muddy, and as the car traverses it, its wheels
get partially stuck, resulting in a coefficient of friction of 0.40 between the car and the slope. The
total amount of work does the tow truck with it winch have to do on the car to pull the car the final
8.00 m up the slope is closest to.
Answer: 73kJ
Just as the car gets close to the top of the embankment, the tow rope breaks, and the car starts to roll back down the embankment, traversing the full length of both the muddy and the dry portions of the slope. What is the speed of the car when it hits the bottom, 30.0 m down the slope?
Answer: 15.5 m/s
A bowl has a hemispherical inside surface with radius R = 15 cm, and is sitting in the exact center of a spinning table that complete one full turn in 0.72 s. A small marble is dropped into the bowl. After the marble has stopped rolling around, it will come to rest against the inside surface of the bowl, rotating around the center of the table at the same rate as the bowl. You can ignore the size of the marble. The angle theta , as defined in the figure, is closest to
Answer:31 degrees
I have the answers, but I do not know how to do them. Thanks for the help!
Answer: 22cm
For the final 8.00 m of the embankment, the ground is muddy, and as the car traverses it, its wheels
get partially stuck, resulting in a coefficient of friction of 0.40 between the car and the slope. The
total amount of work does the tow truck with it winch have to do on the car to pull the car the final
8.00 m up the slope is closest to.
Answer: 73kJ
Just as the car gets close to the top of the embankment, the tow rope breaks, and the car starts to roll back down the embankment, traversing the full length of both the muddy and the dry portions of the slope. What is the speed of the car when it hits the bottom, 30.0 m down the slope?
Answer: 15.5 m/s
A bowl has a hemispherical inside surface with radius R = 15 cm, and is sitting in the exact center of a spinning table that complete one full turn in 0.72 s. A small marble is dropped into the bowl. After the marble has stopped rolling around, it will come to rest against the inside surface of the bowl, rotating around the center of the table at the same rate as the bowl. You can ignore the size of the marble. The angle theta , as defined in the figure, is closest to
Answer:31 degrees
I have the answers, but I do not know how to do them. Thanks for the help!
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I'm so boned for the test tomorrow...
Anyways I figured out how to do the first two:
Power=Force*Velocity
1200=mgsin(30)*v
=.22m
When you get to the rough patch, you see that there is another force added -- force of friction
we know it's (u_k)n which = .4mgcos(30)
you add this to the force of gravity and multiply these by the distance (8m)
8m(mgsin(30)+.4mgcos(30))
gives you 73000 or so.
Can't seem to find out how to do the second to last one and I don't think anything like the last one will be on the test.
Anyways I figured out how to do the first two:
Power=Force*Velocity
1200=mgsin(30)*v
=.22m
When you get to the rough patch, you see that there is another force added -- force of friction
we know it's (u_k)n which = .4mgcos(30)
you add this to the force of gravity and multiply these by the distance (8m)
8m(mgsin(30)+.4mgcos(30))
gives you 73000 or so.
Can't seem to find out how to do the second to last one and I don't think anything like the last one will be on the test.
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No diagrams - no answers