Exam 4: Dynamics: Newtons Laws of Motion

A 15-kg block is on a frictionless ramp that is inclined a ° above the horizontal. It is connected by a very light string over an ideal pulley at the top edge of the ramp to a hanging 19-kg block, as Shown in the figure. The string pulls on the 15-kg block parallel to the surface of the ramp. Find the Magnitude of the acceleration of the 19-kg block after the system is gently released?

Three boxes are pulled along a horizontal frictionless floor by a constant horizontal pull P . The boxes are connected by very light horizontal strings having tensions as shown in the figure. Which of the following statements about the tensions is correct? (There could be more than one correct choice.)

The figure shows an acceleration-versus-force graph for a 125-g object. What should be the value of the first tick-mark on the vertical scale, as indicated by the arrow in the figure?

A 200-N sled of slides down a frictionless hillside that rises at 3 bove the horizontal. What is the magnitude of the force that the surface of the hill exerts on the sled?

A fireman is sliding down a fire pole. As he speeds up, he tightens his grip on the pole, thus increasing the vertical frictional force that the pole exerts on the fireman. When the force on his Hands equals his weight, what happens to the fireman?

A 1000-kg barge is being towed by means of two horizontal cables. One cable is pulling with a force of 80.0 N in a direction 30.0° west of north. In what direction should the second cable pull so That the barge will accelerate northward, if the force exerted by the cable is 120 N? Assume that the Water exerts no appreciable frictional drag on the barge.

The coefficients of static and kinetic friction between a 3.0-kg box and a horizontal desktop are 0.40 and 0.30, respectively. What is the force of friction on the box when a 15-N horizontal push is Applied to the box?

A 30.0-kg load is being held in place using massless wires in the ideal pulley arrangement shown in the figure. What is the magnitude of the force F?

A push of magnitude P acts on a box of weight W as shown in the figure. The push is directed at an angle $\theta$ below the horizontal, and the box remains a rest. The box rests on a horizontal surface that has some friction with the box. The normal force on the box due to the floor is equal to

The figure shows a block of mass m resting on a slope. The block has coefficients of friction with the surface of the slope. It is connected using a very light string over an ideal pulley to a hanging block of mass 2.0 kg. The string above the slope pulls parallel to the surface. What is the minimum mass m so the system will remain at rest when it is released from rest?

A load is being lifted vertically upwards by means of two cables attached to it. The first cable exerts a force of 600 N at an angle of 35.0° to the left of the vertical. The second cable exerts a force Of 1300 N. At what angle to the right of the vertical is the second cable pulling?

In order to get an object moving, you must push harder on it than it pushes back on you.

In the figure, block A has a mass of 3.00 kg. It rests on a smooth horizontal table and is connected by a very light horizontal string over an ideal pulley to block B, which has a mass of 2.00 kg. When Block B is gently released from rest, how long does it take block B to travel 80.0 cm?

In a collision between a huge SUV and a small hybrid car, the SUV exerts a larger force on the hybrid than the hybrid exerts on the SUV.

A horse pulls a cart with force $\vec { F }$ As a result of this force the cart accelerates with constant acceleration. The magnitude of the force that the cart exerts on the horse

A 7.5-kg stone moves up frictionless hill that slopes upward at above the horizontal. If the stone has an initial velocity of 8.5 m/s at the bottom, how far (as measured along the surface of the hill) will it go before stopping?

In the figure, a 10-lb weight is suspended from two spring scales, each of which has negligible weight. Which one of the following statements about the readings in the scales is true?

Bill and his daughter Susan are both standing on identical skateboards (with really good frictionless ball bearings), initially at rest. Bill weighs three times as much as Susan. Bill pushes Horizontally on Susan's back, causing Susan to start moving away from Bill. Just after Bill stops Pushing,

You pull on a crate with a rope. If the crate moves, the rope's pull on the crate must have been larger than the crate's pull on the rope, but if the crate does not move, both of these pulls must have been equal.

In order to lift a bucket of concrete, you must pull up harder on the bucket than the bucket pulls down on you.