A block of mass m = 0.04 kg slides across a frictionless horizontal surface with an initial speed of v = 2.9 m/ s. It stops when it collides and compresses a spring that is attached to a wall. How much will the spring compress if the force constant k is 145 N / m?

7.43 - A 2.0-kg piece of Figure P7.43 wood slides on a curved surface Wood (Fig. P7.43). The sides of the surface are perfectly smooth, but the rough horizontal bottom is 30 m long and has a kinetic friction coefficient of 0.20 with the wood. The piece of wood starts from rest 4.0 m above the rough bottom. (a) Where will this wood eventually come to rest? (b) For the motion from the initial release until the piece of wood comes to rest, what is the total amount of work done by friction? Rough bottom

The spring in the muzzle of a child's spring gun has a spring constant of 705 N/m. To shoot a ball from the gun, first the spring is compressed and then the ball is placed on it. The gun's trigger then releases the spring, which pushes the ball through the muzzle. The ball leaves the spring just as it leaves the outer end of the muzzle. When the gun is inclined upward by 30° to the horizontal, a 57 g ball is shot to a maximum height of 1.84 m above the gun's muzzle. Assume air drag on the ball is negligible. (a) At what speed does the spring launch the ball? m/s (b) Assuming that friction on the ball within the gun can be neglected, find the initial compression distance of the spring. m

An object of mass ?=8.9 kg is free to move on a horizontal surface without any friction. It is initially at rest and starts moving under a net force of ?⃗=(3 N)?̂+(4 N)?̂. What is the object's speed in m/s after moving 1 meter?

A person is crossing a bridge. The bridge is 3.2 meters long and is 25 kg. One side of the bridge rests on the ground while the other side of the bridge is elevated 25 degrees above the ground. The end of the bridge that is elevated is connected to a rope, which is attached to a overhanging section of a cliff. The person walking across is 62 kg, and walks three quarters of the way to the rope end of the bridge then stops. Please determine the magnitude of the force that the ground exerts on the bridge. (use image for reference)

A 5.00-kg block is moving at 5.00 m/s along a horizontal frictionless surface toward an ideal massless spring that is attached to a wall. After the block collides with the spring, it keeps moving rightwards until the spring reaches its maximum compression of 1.68 m. After reaching maximum compression, the block and spring come to rest momentarily, and then move leftwards. While it is moving to the left, what is the speed of the block when it has moved so that the spring is compressed to only one-half of the maximum distance?

You push a box of mass 21.4 kg with your car up to an icy hill slope of irregular shape to a height 5.1 m. The box has a speed 13.3 m/s when it starts up the hill, the same time that you brake. It then rises up to the top (with no friction) to a flat area before elastically colliding with a smaller box of mass 14 kg. The boxes then fall off a sheer cliff individually to the ground (with no drag). (a) How far from the cliff does the heavier box hit the ground? (b) What is the direction of motion of the heavier box as it hits the ground? = ŷ + 2 (c) How far from the cliff does the lighter box hit the ground? (d) What is the direction of motion of the lighter box as it hits the ground? W = ŷ + 2

Sam is shooting a 10 kg rock using a catapult. The posts are 2 m apart and have an unstretched elastic band of the same length between them. The rock and band are pulled back by 1.5 m, which requires a force of 2000 N at the furthest point. How fast will the rock move when released?

A massless spring with spring constant k = 400N/m is placed on a platform which is inclined with angle 0 above the horizontal. A block of mass 1kg is attached to the spring and the spring is compressed by 20cm as shown in the figure. There is no friction between the block and the platform. Find the speed of the block as it travels a distance of 30cm along the platform after it is released. (Take g = 10m/s² and sin 0 = 2/3). m = Select one: О а. 3 m/s O b. 1 m/s k m O c. 5 /ms www O d. 4 m/s О е. 2 m/s

At the instant r = 2 m, the 8-kg disk is given a speed of v = 8 m/s, perpendicular to the elastic cord. Determine the speed of the disk at the instant r=1.1 m. The disk slides on the smooth horizontal plane. Neglect its size. The cord has an unstretched length of 0.5 m. k= 200 N/m B