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Hello....
Any help would be appreciated...
1)Block A in the figure weighs 69.9N . The coefficient of static friction between the block and the surface on which it rests is 0.29. The weight w is 12.2N and the system is in equilibrium.
a)Find the friction force exerted on block A.
b)Find the maximum weight for which the system will remain in equilibrium.
2)A 200 g hockey puck is launched up a metal ramp that is inclined at a 30° angle. The coefficients of static and kinetic friction between the hockey puck and the metal ramp are μs = 0.40 and μk = 0.30, respectively. The puck's initial speed is 7.8 m/s. What speed does it have when it slides back down to its starting point?
3) You are lowering two boxes, one on top of the other, down the ramp...by pulling on a rope parallel to the surface of the ramp. Both boxes move together at a constant speed of 20.0cm/s . The coefficient of kinetic friction between the ramp and the lower box is 0.417, and the coefficient of static friction between the two boxes is 0.753.
a) What force do you need to exert to accomplish this?
b) What is the magnitude of the friction force on the upper box?
c) What is the direction of the friction force on the upper box?
4)A 1600kg rocket is to be launched with an initial upward speed of 51.0m/s . In order to assist its engines, the engineers will start it from rest on a ramp that rises 53 ∘ above the horizontal (the figure (Figure 1) ). At the bottom, the ramp turns upward and launches the rocket vertically. The engines provide a constant forward thrust of 2000 N, and friction with the ramp surface is a constant 500 N.How far from the base of the ramp should the rocket start, as measured along the surface of the ramp?
5)A ball is thrown upward with an initial velocity of 14.0m/s at an angle of 55.0∘ above the horizontal.Use energy conservation to find the ball's greatest height above the ground.
6)A sled with rider having a combined mass of 130kg travels over the perfectly smooth icy hill shown in the accompanying figure.How far does the sled land from the foot of the cliff?
7) A hunter on a frozen, essentially frictionless pond uses a rifle that shoots 4.20g bullets at 950m/s . The mass of the hunter (including his gun) is 69.5kg , and the hunter holds tight to the gun after firing it.
a)Find the recoil speed of the hunter if he fires the rifle horizontally.
b)Find the recoil speed of the hunter if he fires the rifle at 58.0∘ above the horizontal.
8)Two ice skaters, Daniel (mass 70.0kg ) and Rebecca (mass 45.0kg ), are practicing. Daniel stops to tie his shoelace and, while at rest, is struck by Rebecca, who is moving at 12.0m/s before she collides with him. After the collision, Rebecca has a velocity of magnitude 7.00m/s at an angle of 54.1∘ from her initial direction. Both skaters move on the frictionless, horizontal surface of the rink.
a)What is the magnitude of Daniel's velocity after the collision?
b)What is the direction of Daniel's velocity after the collision?
c)What is the change in total kinetic energy of the two skaters as a result of the collision?
9) A steel ball with mass 42.0g is dropped from a height of 1.90m onto a horizontal steel slab. The ball rebounds to a height of 1.64m .
a) Calculate the impulse delivered to the ball during impact.
b) If the ball is in contact with the slab for a time of 1.70ms , find the average force on the ball during impact.
10) A computer disk drive is turned on starting from rest and has constant angular acceleration.
a)If it took 0.820s for the drive to make its second complete revolution, how long did it take to make the first complete revolution?
b)What is its angular acceleration, in rad/s^2?
11)While spinning down from 500.0 rpm to rest, a solid uniform flywheel does 2.3 kJ of work. If the radius of the disk is 1.2 m, what is its mass?
I know these are a lot.....but i am really stuck with them and my homework is due in 2 days .... urgent help required......Thank you......
Any help would be appreciated...
1)Block A in the figure weighs 69.9N . The coefficient of static friction between the block and the surface on which it rests is 0.29. The weight w is 12.2N and the system is in equilibrium.
a)Find the friction force exerted on block A.
b)Find the maximum weight for which the system will remain in equilibrium.
2)A 200 g hockey puck is launched up a metal ramp that is inclined at a 30° angle. The coefficients of static and kinetic friction between the hockey puck and the metal ramp are μs = 0.40 and μk = 0.30, respectively. The puck's initial speed is 7.8 m/s. What speed does it have when it slides back down to its starting point?
3) You are lowering two boxes, one on top of the other, down the ramp...by pulling on a rope parallel to the surface of the ramp. Both boxes move together at a constant speed of 20.0cm/s . The coefficient of kinetic friction between the ramp and the lower box is 0.417, and the coefficient of static friction between the two boxes is 0.753.
a) What force do you need to exert to accomplish this?
b) What is the magnitude of the friction force on the upper box?
c) What is the direction of the friction force on the upper box?
4)A 1600kg rocket is to be launched with an initial upward speed of 51.0m/s . In order to assist its engines, the engineers will start it from rest on a ramp that rises 53 ∘ above the horizontal (the figure (Figure 1) ). At the bottom, the ramp turns upward and launches the rocket vertically. The engines provide a constant forward thrust of 2000 N, and friction with the ramp surface is a constant 500 N.How far from the base of the ramp should the rocket start, as measured along the surface of the ramp?
5)A ball is thrown upward with an initial velocity of 14.0m/s at an angle of 55.0∘ above the horizontal.Use energy conservation to find the ball's greatest height above the ground.
6)A sled with rider having a combined mass of 130kg travels over the perfectly smooth icy hill shown in the accompanying figure.How far does the sled land from the foot of the cliff?
7) A hunter on a frozen, essentially frictionless pond uses a rifle that shoots 4.20g bullets at 950m/s . The mass of the hunter (including his gun) is 69.5kg , and the hunter holds tight to the gun after firing it.
a)Find the recoil speed of the hunter if he fires the rifle horizontally.
b)Find the recoil speed of the hunter if he fires the rifle at 58.0∘ above the horizontal.
8)Two ice skaters, Daniel (mass 70.0kg ) and Rebecca (mass 45.0kg ), are practicing. Daniel stops to tie his shoelace and, while at rest, is struck by Rebecca, who is moving at 12.0m/s before she collides with him. After the collision, Rebecca has a velocity of magnitude 7.00m/s at an angle of 54.1∘ from her initial direction. Both skaters move on the frictionless, horizontal surface of the rink.
a)What is the magnitude of Daniel's velocity after the collision?
b)What is the direction of Daniel's velocity after the collision?
c)What is the change in total kinetic energy of the two skaters as a result of the collision?
9) A steel ball with mass 42.0g is dropped from a height of 1.90m onto a horizontal steel slab. The ball rebounds to a height of 1.64m .
a) Calculate the impulse delivered to the ball during impact.
b) If the ball is in contact with the slab for a time of 1.70ms , find the average force on the ball during impact.
10) A computer disk drive is turned on starting from rest and has constant angular acceleration.
a)If it took 0.820s for the drive to make its second complete revolution, how long did it take to make the first complete revolution?
b)What is its angular acceleration, in rad/s^2?
11)While spinning down from 500.0 rpm to rest, a solid uniform flywheel does 2.3 kJ of work. If the radius of the disk is 1.2 m, what is its mass?
I know these are a lot.....but i am really stuck with them and my homework is due in 2 days .... urgent help required......Thank you......
