Exam 10: Motion in a Plane

A ball is thrown at a 60.0° angle above the horizontal across level ground. It is thrown from a height of 2.00 m above the ground with a speed of 20.0 m/s and experiences no appreciable air resistance.The time the ball remains in the air before striking the ground is closest to

Jason takes off from rest across level water on his jet-powered skis.The combined mass of Jason and his skis is 75 kg (the mass of the fuel is negligible).The skis have a thrust of 200 N and a coefficient of kinetic friction on water of 0.10.Unfortunately,the skis run out of fuel after only 48 s.What is Jason's top speed?

If A > B,under what condition is | - | = A - B?

A projectile returns to its original height 4.08 s after being launched,during which time it travels 76.2 m horizontally.If air resistance can be neglected,what was the projectile's initial speed?

If = +4 - 2 - 3 And = -4 -2 - 3 ,which of the following numbers is closest to the magnitude of - ?

A student slides her 80.0-kg desk across the level floor of her dormitory room a distance 4.00 m at constant speed. If the coefficient of kinetic friction between the desk and the floor is 0.400,how much work did she do?

A hockey puck slides off the edge of a table with an initial velocity of 28.0 m/s.and experiences no air resistance.The height of the tabletop above the ground is 2.00 m.What is the angle below the horizontal of the velocity of the puck just before it hits the ground?

A firecracker breaks up into several pieces,one of which has a mass of 200 g and flies off along the X-axis with a speed of 82.0 m/s.A second piece has a mass of 300 g and flies off along the y-axis with a speed of 45.0 m/s.What are the magnitude and direction of the total momentum of these two pieces?

If the magnitude of vector is less than the magnitude of vector ,then the x component of is less than the x component of .

The following four forces act on a 4.00 kg object: ₁ = 300 N east ₂ = 700 N north ₃ = 500 N west ₄ = 600 N south What is the acceleration of the object?

A pool player is attempting a fancy shot.He hits the cue ball giving it a speed of 5.57 m/s and directs its center on a path tangent to the surface of the target ball having the same mass as the cue ball.After the collision (on a frictionless table)the initially-stationary ball moves with a speed of 4.82 m/s.After the collision,the new speed of the cue ball and the relative direction of the balls are closest to

A catapult is tested by Roman legionnaires.They tabulate the results in a papyrus and 2000 years later the archaeological team reads (distances translated into modern units): Range = 0.20 km; Angle of launch = π/4; landing height = launch height.What is the initial velocity of launch of the boulders if air resistance is negligible?

A packing crate rests on a horizontal surface.It is acted on by three horizontal forces: 600 N to the left,200 N to the right,and friction.The weight of the crate is 400 N.If the 600-N force is removed,the resultant force acting on the crate is

For the vectors shown in the figure,assume numbers are accurate to two significant figures. The scalar product × Is closest to

The components of vector are A_x = +2.2 and A_y = -6.9,and the components of vector Are given are B_x = -6.1 and B_y = -2.2.What is the magnitude of the vector - ?

The magnitude of a vector can never be less than the magnitude of one of its components.

Vector = -1.00 + -2.00 And vector = 3)00 + 4)00 What are the magnitude and direction of vector = 3)00 + 2)00 ?

A rope pulls on the lower block in the figure with a tension force of 20 N.The coefficient of kinetic friction between the lower block and the surface is 0.16.The coefficient of kinetic friction between the lower block and the upper block is also 0.16.The pulley has no appreciable mass or friction.What is the acceleration of the 2.0 kg block?

A 50.0-kg box rests on a horizontal surface.The coefficient of static friction between the box and the surface is 0.300 and the coefficient of kinetic friction is 0.200.What is the friction force on the box if (a) a horizontal 140-N push is applied to it? (b) a horizontal 175-N push is applied to it?

A driver in a 1000 kg car traveling at 20 m/s slams on the brakes and skids to a stop.If the coefficient of friction between the tires and the horizontal road is 0.80,how long will the skid marks be?