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100
The work done if a force of 15 N is applied on a ball which travels 5 m. The angle between these vectors is 90 degrees.
What is 0 J?
100
State the equation for conservation of energy.
deltaU + deltaK + f1sdeltas= Wext or 0 if no external work.
100
State whether momentum a vector or a scalar. What is impulse (two answers)?
What is scalar? Ft and delta p?
100
State the units of Torque. state the units of angular momentum.
what are kg m2/s2 and kgm2/s?
100
A hoop of r 5m and m 5 kg rolls without slipping on a horizontal surface. State the relationship between its translational kinetic energy and its total kinetic energy.
What is ktrans= 1/5ktot?
200
The work done after a Force of 5i - 2j +1k N acts on an object which travels the distance 1i - 6j + 2k N.
What is 19 J?
200
Block 1 (M) and Block 2 (2M) slide across a frictionless floor. They have the same kinetic energy when they encounter a rough stretch, which slows them to a stop. State the relationship between the stopping distances s2 and s1
What is s2=s1/2?
200
Puck 1 (1 kg) travels with velocity 20 m/s to the right when it collides with puck 2 (1 kg) which is initially at rest. After the collision, puck 1 moves with a velocity of 5 m/s. Assume that no external forces are present and therefore the momentum for the system of pucks is conserved. State the final momentum of puck 2 after the collision.
15m/s
200
A ring and a solid sphere are placed beside each other at the top of an inclined ramp. They are both released at the same time and roll without slipping down the ramp. State which will reach the bottom first.
What is the sphere?
200
A lighter and a heavier block sit on a frictionless surface. Both blocks are initially at rest, The same force F pushes to the right on each block for 1 meter. state which block has the larger final kinetic energy after the force acts.
What is same?
300
Starting from rest a 6 kg ball experience a force of 3 N and travels 6 m in the same direction as the force. State the final kinetic energy of the ball. Also state the final velocity.
What is k=18 j and v=sqrt(6)?
300
On a frictionless surface, a box is pushed against a fixed spring and compresses it a distance x1 from its relaxed position. When the box is released, it slides away from the spring with velocity v1. If the spring were compressed to seven times the distance (i.e., x2 = 7 x1), then what would be the new velocity v2 of the box?
What is v2=7v1?
300
A 0.5-kg ball in the air has an initial velocity vo = [ -40 ] i + [ -40 ] j m/s. It falls for a total time of 1 s. Statethe initial momentum pi of the ball, delta p, pf, ki, kf, and delta k.
What is pi= -20i -20 kgm/s pf= -20i -25j kgm/s delta p=0i-5j kgm/s ki=800j kf=1025 delta k = 225j?
300
A girl sitting on a bar stool with two equal masses in her outstretched arms is rotating counterclockwise at a speed of ω. She slowly brings her arms directly towards her body and as a result her angular speed increases. Explain how the inertia is affected before and after she brings her arms in. State which direction the force applied by her arms is, and whether there is an external torque.
What is I=BMR^2 (r decreases) and the F is radially inward with no external torque?
400
A ball of mass m is thrown to height h. State the work done by gravity.
What is -mgh.
400
A block slides down a frictionless incline plane of height h. At the bottom of the incline, it compresses a spring by a distance x1 and momentarily stops moving. State the relationship between the compression distance x1 if the block has fallen a height h and the distance x2 if the block has fallen a height 5h.
What is x2=sqrt(5)x1?
400
A railgun uniformly accelerates a 20-kg cart along a 1D track from 10 m/s to 40 m/s with a net force of 300 N. State the magnitude of the impulse delivered to the cart during this time period.State how long it took the cart to speed up from 10 m/s to 40 m/s. State the initial and final kinetic energies and the net work, and how far the car traveled.
What is 600 kgm/s, 2s, 1000, and 16000j, W=15000 j, 50m?
400
A ring of mass 2 M and radius 2 R rotates in a CCW direction with initial angular speed 1 ω. A disk of mass 4 M and radius 2 R rotates in a CW direction with initial angular speed 2 ω. The ring and disk "collide" and eventually rotate together. Assume that positive angular momentum and angular velocity values correspond to rotation in the CCW direction. state ωf of the system.
What is -.5ω?
500
A box is pulled by a string with horizontal force T across a horizontal, frictionless table. IF the box starts from rest, state the relationship between speed v1 after the box has moved a distance d, and the speed v2 after the box has move 5d.
What is v2=sqrt(5)v1?
500
A lighter block and a heavier block sit on a frictionless surface.The LIGHTER block is AT REST, while the HEAVIER block has an INITIAL VELOCITY to the right. The same force F then pushes to the right on each block for 1 meter. State which block has the larger final kinetic energy after the force acts. State which block has the larger final momentum after the force acts. If there is insuffient info please state this.
What are heavier and insufficient information?
500
A 1300-kg car travels at 30 m/s and then quickly stops in 3.6 s to avoid an obstacle.State the magnitude of the impulse necessary to stop the car, the magnitude of the average force in kiloNewtons (kN) that stopped the car, and the avergage accelertion magnitude.
What is 39000 kgm/s, 10.8 kN, and 8.3 m/s^2?
500
A kid runs towards the edge of a merry-go-round that is not rotating and jumps on. The merry-go-round then rotates with a constant angular velocity ω. Assume that the kid has a mass of 40 kg and is initially running at a speed of 4 m/s tangent to the edge of the merry-go-round. The merry-go-round is a uniform disk with a mass of 100 kg and a radius of 2 m. Assume that it rotates without friction.State the final angular velocity ωf of the merry-go-round (with the kid riding).
What is .889 rad/s?