Please help me!!
our teacher put up these review problems and i don't know how to do them!!! this is not good!!!
From the top of a tall building, a gun is fired. The bullet leaves the gun at a speed of 340 m/s, parallel to the ground. As the drawing shows, the bullet puts a hole in a window of another building and hits the wall that faces the window. (y = 0.58 m, and x = 5.7 m.) Using the data in the drawing, determine the distances D and H, which locate the point where the gun was fired. Assume that the bullet does not slow down as it passes through the window.
H = m
D = m
A person looking out the window of a stationary train notices that raindrops are falling vertically down at a speed of 3.5 m/s relative to the ground. When the train moves at a constant velocity, the raindrops make an angle of 38° when they move past the window. How fast is the train moving?
A diver springs upward from a board that is three meters above the water. At the instant she contacts the water her speed is 9.00 m/s and her body makes an angle of 84.0° with respect to the horizontal surface of the water. Determine her initial velocity, both magnitude and direction.
To hoist himself into a tree, a 68.5 kg man ties one end of a nylon rope around his waist and throws the other end over a branch of the tree. He then pulls downward on the free end of the rope with a force of 382 N. Neglect any friction between the rope and the branch, and determine the man's upward acceleration.
For the normal force in Figure 5.21 to have the same magnitude at all points on the vertical track, the stunt driver must adjust the speed to be different at different points. Suppose, for example, that the track has a radius of 3.5 m and that the driver goes past a point at the bottom with a speed of 17 m/s. What speed must she have at the very top, so that the normal force at the top has the same magnitude as it did at the bottom?
A 56.0 kg. skateboarder starts out with a speed of 1.80 m/s. He does +80.0 J of work on himself by pushing with his feet against the ground. In addition, friction does -265 J of work on him. In both cases, the forces doing the work are nonconservative. The final speed of the skateboarder is 6.15 m/s.
(a) Calculate the change (ΔPE = PEf - PE0) in the gravitational potential energy.
J
(b) How much has the vertical height of the skater changed?
A lumberjack (mass = 98 kg) is standing at rest on one end of a floating log (mass = 255 kg) that is also at rest. The lumberjack runs to the other end of the log, attaining a velocity of +3.4 m/s relative to the shore, and then hops onto an identical floating log that is initially at rest. Neglect any friction and resistance between the logs and the water.
(a) What is the velocity of the first log just before the lumberjack jumps off? (Indicate the direction of the velocity by the sign of your answers.)
m/s
(b) Determine the velocity of the second log if the lumberjack comes to rest on it.
A 0.023 kg bullet is fired straight up at a falling wooden block that has a mass of 3.0 kg. The bullet has a speed of 780 m/s when it strikes the block. The block originally was dropped from rest from the top of a building and had been falling for a time t when the collision with the bullet occured. As a result of the collision, the block (with the bullet in it) reverses direction, rises, and comes to a momentary halt at the top of the building. Find the time t.
Two balls are approaching each other head-on. Their velocities are +10.40 and -11.0 m/s.
(a) Determine the velocity of the center of mass of the two balls if they have the same mass.
m/s
(b) Determine the velocity of the center of mass of the two balls if the mass of one ball (v = 10.40 m/s) is twice the mass of the other ball (v = -11.0 m/s).
ANY HELP AT ALL WOULD BE AMAZING
THANK YOU
our teacher put up these review problems and i don't know how to do them!!! this is not good!!!
From the top of a tall building, a gun is fired. The bullet leaves the gun at a speed of 340 m/s, parallel to the ground. As the drawing shows, the bullet puts a hole in a window of another building and hits the wall that faces the window. (y = 0.58 m, and x = 5.7 m.) Using the data in the drawing, determine the distances D and H, which locate the point where the gun was fired. Assume that the bullet does not slow down as it passes through the window.
H = m
D = m
A person looking out the window of a stationary train notices that raindrops are falling vertically down at a speed of 3.5 m/s relative to the ground. When the train moves at a constant velocity, the raindrops make an angle of 38° when they move past the window. How fast is the train moving?
A diver springs upward from a board that is three meters above the water. At the instant she contacts the water her speed is 9.00 m/s and her body makes an angle of 84.0° with respect to the horizontal surface of the water. Determine her initial velocity, both magnitude and direction.
To hoist himself into a tree, a 68.5 kg man ties one end of a nylon rope around his waist and throws the other end over a branch of the tree. He then pulls downward on the free end of the rope with a force of 382 N. Neglect any friction between the rope and the branch, and determine the man's upward acceleration.
For the normal force in Figure 5.21 to have the same magnitude at all points on the vertical track, the stunt driver must adjust the speed to be different at different points. Suppose, for example, that the track has a radius of 3.5 m and that the driver goes past a point at the bottom with a speed of 17 m/s. What speed must she have at the very top, so that the normal force at the top has the same magnitude as it did at the bottom?
A 56.0 kg. skateboarder starts out with a speed of 1.80 m/s. He does +80.0 J of work on himself by pushing with his feet against the ground. In addition, friction does -265 J of work on him. In both cases, the forces doing the work are nonconservative. The final speed of the skateboarder is 6.15 m/s.
(a) Calculate the change (ΔPE = PEf - PE0) in the gravitational potential energy.
J
(b) How much has the vertical height of the skater changed?
A lumberjack (mass = 98 kg) is standing at rest on one end of a floating log (mass = 255 kg) that is also at rest. The lumberjack runs to the other end of the log, attaining a velocity of +3.4 m/s relative to the shore, and then hops onto an identical floating log that is initially at rest. Neglect any friction and resistance between the logs and the water.
(a) What is the velocity of the first log just before the lumberjack jumps off? (Indicate the direction of the velocity by the sign of your answers.)
m/s
(b) Determine the velocity of the second log if the lumberjack comes to rest on it.
A 0.023 kg bullet is fired straight up at a falling wooden block that has a mass of 3.0 kg. The bullet has a speed of 780 m/s when it strikes the block. The block originally was dropped from rest from the top of a building and had been falling for a time t when the collision with the bullet occured. As a result of the collision, the block (with the bullet in it) reverses direction, rises, and comes to a momentary halt at the top of the building. Find the time t.
Two balls are approaching each other head-on. Their velocities are +10.40 and -11.0 m/s.
(a) Determine the velocity of the center of mass of the two balls if they have the same mass.
m/s
(b) Determine the velocity of the center of mass of the two balls if the mass of one ball (v = 10.40 m/s) is twice the mass of the other ball (v = -11.0 m/s).
ANY HELP AT ALL WOULD BE AMAZING
THANK YOU