Newton's law of motion Questions and Answers

A car has a mass of 1.10 x 10³ kg. If the force acting on the car is 6.84 × 10³ N to the east, what is the car's acceleration? Answer in units of m/s².

A 50.0 kg woman, riding on a 10 kg cart, is moving east at 5.0 m/s. The woman jumps off the front of the cart and lands on the ground at 7.0 m/s eastward. What is the final velocity of the cart? (4.6 m/s westward or -4.6 m/s)

A 1250 kg car is moving down the highway with a velocity of 32.0 m/s when it bumps into the car ahead of it which has a mass of 875 kg and a velocity of 25.0 m/s. After the collision, the two cars stick together. What will be the resulting velocity of the two cars together? How much energy will be lost in this collision? (29.1 m/s, 13702 J)

tension in wire thin adhesive film between blocks ⒸWbottom - Fadhesion OT-Wbottom+Wtop + Fadhesion OT-Wtop - Fadhesion OWtop - T K As shown above an adhesive has been applied to contacting faces of two blocks so that the blocks interact with an adhesive force that has a magnitude, Fadhession- A tension, T, is exerted by a wire attached to the upper blocks causing the blocks to remain at rest. The two blocks have weights, Wbottom and Wtop. Which of the following must be true? (1 point)

A car carrying a 75-kg test dummy crashes into a wall at 26 m/s and is brought to rest in 0.10 s. What is the magnitude of the average force exerted by the seat belt on the dummy? Express your answer to two significant figures and include the appropriate units,

Suppose a cart is being moved by a certain net force. If a load is dumped into the cart so its mass is changed by a factor of 1, by what factor does the acceleration change if the net force remains the same?

A house is lifted from its foundation onto a truck for relocation. The house is pulled upward by net force of 2850 N. This force causes the house to move from rest to an upward speed of 0.15 m/s in 5 s. What is the mass of the house?

Solve the problem. While traveling in a car, the centrifugal force a passenger experiences as the car drives in a circle varies jointly as the mass of the passenger and the square of the speed of the car. If a passenger experiences a force of 21.6 newtons when the car is moving at a speed of 20 kilometers per hour and the passenger has a mass of 60 kilograms, find the force a passenger experiences when the car is moving at 40 kilometers per hour and the passenger has a mass of 100 kilograms. 176 newtons 144 newtons 128 newtons 160 newtons

Two horizontal forces are acting on a chunk of wood of mass m = 0.333 kg sitting on ice, as shown. The diagram shows the forces viewed from above. F₁ 30.0 N (east), F₂is 40.0 N (north). The magnitude fo the acceleration of the wood is 150 m/s2. To 3-place precision, what is the magnitude of the net force on the wood? (Assume that friction is small enough to ignore.) 70.0 N 10.0 N 50.0 N 0.47 N 0.33 N

A person in an elevator is holding a 10.1 kg block by a cord rated to withstand a tension of 158 N. When the elevator starts up, the cord breaks. The acceleration of gravity is 9.81 m/s². What was the minimum acceleration of the elevator? Answer in units of m/s².

What must the tension be in the cable to stop this elevator over a distance of 2.5 m if the elevator has a mass of 1500 kg including occupants? Express your answer to three significant figures and include the appropriate units.

A 12 kg mass travels to the right with velocity of 5.5 m/s while another mass of 6 kg also travels to the right with a velocity of 2 m/s. Afterwards the 12 kg mass still travels to the right but with the velocity of 1.5 m/s. What Momentum was transferred to the smaller mass?

A 350 kg rubber mass collides with a wall while travelling towards the wall at 20 m/s. Afterwards the mass is seen travelling in the opposite direction from the wall also at 20 m/s. The force applied to the wall by the rubber mass and that caused the change in momentum occurred in 0.2 seconds. What was the Force?

In the design of a super market, there are to be several ramps connecting different parts of the store. Customers will have to push grocery carts up ramps and it is obviously desired that this not be too difficult. An engineer has done a survey and found that almost no one complains if the force required is no more that 50 N. Will a slope of 5 degrees be too steep, assuming a 30 Kg cart with groceries? Assume that all friction can be accounted for with a kinetic friction coefficient of 0.10.

Lucy holds a football in place by pressing down on it with a force of 10 N while Charlie Brown attempts to kick it. The mass of the football is 2 kg and the coefficient of static friction between the football and the ground is 0.89. Assuming Lucy does not pull the ball away, what minimum horizontal force must Charlie Brown apply to the football in order to move it?

A 29kg stone is lifted 1.5m by a force that is only 71N. a. What is the mechanical advantage of the system? b. If the force is applied over 6.2m, what is the efficiency of the system?

A rocket is launched at an angle of 0= 53° above the horizontal with an initial speed v= 80 m/s, as shown below. It moves for 25 s along its initial line of motion wth an acceleration of 25.2 m/s². At this time, its engines fail and the rocket proceeds to move as a free body. (a) What is the rocket's maximum altitude? (b) What is the rocket's total time of flight? (c) What is the rocket's horizontal range?

Ball of clay with mass 0.100 kg directly dropped from 1.50 m above the ground. (a) What is the speed of the clay ball just before it hits the ground? (b) If the clay ball stick to the floor after hitting the ground in 0.00250 s, calculate the force on the clay by the floor. (Ignore the gravity) (c) What is the force created on the ground by the clay ball? (Ignore the gravity) (d) Why is the force of gravity not that important for part b and c? (e) Calculate the impulse on the ball (f) Calculate the impulse on the ground.

An object of mass 27.764 kg is being pulled by a horizontal force of 240 N on a horizontal force. The coefficient of kinetic friction between the object and the surface is 0.2. Calculate the acceleration of the object. A. 4.533 m/s² B. 6.684 m/s² C. 12.441 m/s² D. 0.381 m/s E. 0.952 m/s²

An elevator of mass m moving upward has two forces acting on it: the upward force of tension in the cable and the downward force due to gravity. When the elevator is accelerating upward, which is greater, Tor w? (b) When the elevator is moving at a constant velocity upward, which is greater, T or w? (c) When the elevator is moving upward, but the acceleration is downward, which is greater, Tor w? (d) Let the elevator have a mass of 1,350 kg and an upward acceleration of 2.7 m/s². Find T. (e) The elevator of part (d) now moves with constant upward velocity of 10 m/s. Find T.

A block of mass m is connected to another block of mass M by a spring ( massless) of spring constant k. The blocks are kept on a smooth horizontal plane. Initially the blocks are at rest and the spring is unstretched. Then a constant force F starts acting on the block of mass M to pull it. Find the force on the block of mass m.

A block is gently placed on a conveyor belt moving horizontally with constant speed. After t = 4s, the velocity of the block becomes equal to the velocity of the belt. If the coefficient of friction between the block and the belt is = 0.2 then the velocity of the conveyor belt is

A 5.00-m-long ladder, weighing 200 N, rests against a smooth vertical wall with its base on a horizontal rough floor, a distance of 1.20 m away from the wall. The center of mass of the ladder is 2.50 m from its base, and the coefficient of static friction between the ladder and the floor is 0.200. How far up the ladder, measured along the ladder, can a 600-N person climb before the ladder begins to slip? 1.05 m 3.95 m 4.56 m 1.50 m 1.26 m

A light, inextensible cord passes over a light, frictionless pulley with a radius of 8 cm. It has a(n) 19 kg mass on the left and a(n) 4.1 kg mass on the right, both hanging freely. Initially their center of masses are a vertical distance 2.3 m apart. The acceleration of gravity is 9.8 m/s².

A 70 kilogram motorcycle is moving at a speed of 33.75 m/s. a. What is the momentum of the cycle? b. If it stops in 5 seconds, what is the new momentum? c. How much is the change in momentum? d. How much is the impulse? e. Calculate the magnitude and direction of the force

A novice skier, starting from rest, slides down an icy frictionless 11 incline whose vertical height is 140 m How fast is she going when she reaches the bottom? Express your answer to two significant figures and Include the appropriate units.

The center of the moon and the center of the earth are 3.80 x 105 km apart. The mass of the moon is approximately 7.36 x 1022 kg, while earth's mass is about 5.98 x 1024 kg. A) Calculate the earth's pull on the moon. B) What is the size of the moon's pull on the earth? explain or show work

If you were in deep space, far away from anything with gravity, and threw a rock, how much force would have to be exerted on the rock to keep it going at a constant velocity? None, there is nothing in space to slow the rock down. None, the laws of Physics do not apply in space. A little because air friction will slow the rock down. A lot because gravity will slow the rock.

What is the net force acting on Mr. L, who weighs 774 Newtons and is holding a 25 Newton weight if he is in equilibrium? 774 Newtons Zero 799 Newtons 25 Newtons

Calculate the force needed to bring a 913-kg car to rest from a speed of 86.0 km/h in a distance of 129 m (a fairly typical distance for a non-panic stop). Suppose instead the car hits a concrete abutment at full speed and is brought to a stop in 2.02 m. Calculate the force exerted on the car and compare it with the force found previously. What is the absolute magnitude of their difference? Give your answer in newtons with 3 significant figures in scientific notation.

If you were in space with an elephant and a mouse and they were moving toward you with the same velocity, which one would bump into you with more force? The elephant. The mouse. Neither, they have the same inertia.

Dizzy is speeding along at 26.2 m/s as she approaches the level section of track near the loading dock of the Whizzer roller coaster ride. A braking system abruptly brings the 324-kg car (rider mass included) to a speed of 3 m/s over a distance of 5.33 meters. Determine the magnitude of the braking force (in newtons) applied to Dizzy's car.

You pull a 20 kg cart with a force F= 8.0 N directed at 55° with respect to the horizontal (see figure). Neglect friction. The cart acceleration is closest to: 0 m/s² 0.11 m/s² 0.23 m/s² 0.33 m/s2

A 7-kg toboggan is kicked on a frozen pond, such that it acquires a speed of 2.1 m/s to the right. The coefficient of friction between the pond and the toboggan is 0.17. Determine the distance that the toboggan slides before coming to rest. m (round to the nearest hundredth) Answer:

In Fig. 9-63, block 1 (mass 2.0 kg ) is moving rightward at 10 m/s and block 2 (mass 5.0 kg) is moving rightward at 3.0 m/s .The surface is frictionless, and a spring with a spring constant of 1120 N/m is fixed to block 2. When the blocks collide, the compression of the spring is maximum at the instant the blocks have the same velocity. Find the maximum compression. m

Therin sprints through a small canyon when a hiding spider ensnares him in a web. His legs and arms wrapped together, Therin falls to the ground head first and begins to slide along the rocky ground. If Therin weighs 588 N and the coefficient of friction is 0.4, how quickly does the elf accelerate?

Frogs have impressive jumping abilities, capable of jumps covering a horizontal distance of up to 30 times their body length. a) If a frog jumps a distance of 60 cm on a flat surface (at a take-off angle of 45°) then what is its take-off speed v = √vox+vy? The jump took a time of 0.3 s. What is the max height above ground ? Neglect air resistance. b) Why is the max height of the jump different from its horiz. distance, even though the take-off angle is 45° ? Explain. c) During its jump, is the frog in free fall or not? Explain.

An elevator is moving up at a constant velocity of 2.50 m/s, as illustrated in the diagram below: The man has a mass of 65.0 kg. a. Construct a force diagram for the man. b. How large is the force that the floor exerts on the man?

A record of travel along a straight path is as follows: (a) Start from rest with constant acceleration of 2.82 m/s² for 18.8 s; (b) Constant velocity of 53.016 m/s for the next 0.866 min; acceleration of (c) Constant negative -8.96 m/s² for 5.39 s. What was the total displacement x for the complete trip? Answer in units of m.

What is the acceleration of an automobile of mass 1.91 × 103 kg when it is subjected to a net forward force of 3.36 x 103 N? If the acceleration is forward, enter a positive value. If the acceleration is backward, enter a negative value.

Uniform Circular Motion: The curved section of a horizontal highway is a circular unbanked arc of radius 740 m. If the coefficient of static friction between this roadway and typical tires is 0.40, what would be the maximum safe driving speed for this horizontal curved section of highway? 50 m/s 52 m/s 46 m/s 54 m/s 48 m/s

A student stands on a bathroom scale in an elevator at rest on the 64th floor of a building. The scale reads 844 N. As the elevator moves up, the scale reading increases to 948 N, then decreases back to 844 N. The acceleration of gravity is 9.8 m/s². Find the acceleration of the elevator. Answer in units of m/s².

A 9.0-cm-long spring is attached to the ceiling. When a 2.1 kg mass is hung from it, the spring stretches to a length of 18 cm. What is the spring constant k? How long is the spring when a 3.0 kg mass is suspended from it?

A 12.0-kg mass is placed on a 29.0° incline and friction keeps it from sliding. The coefficient of static friction in this case is 0.660, and the coefficient of sliding friction is 0.546. The mass is given a shove causing it to slide down the incline. What is the frictional force while the mass is sliding? 57.0 N 67.9 N 56.2 N 10.5 N 102.9 N

A 112 lb woman puts all of her weight on one heel of her high heel shoes. The heel has an area of 0.37 in². (a) What is the pressure that her heel exerts on the ground in pounds per square inch (PSI)?

When you drop a 0.37 kg apple, Earth exerts a force on it that accelerates it at 9.8 m/s² to- ward the earth's surface. According to New- ton's third law, the apple must exert an equal but opposite force on Earth. If the mass of the earth 5.98 x 1024 kg, what is the magnitude of the earth's acceleration toward the apple? Answer in units of m/s².

Bob the block is placed next to the cylindrical glass wall of an amusement park ride. The cylinder then begins spinning with a constant angular velocity, and spinning Bob remains stuck to the wall even when the floor drops away. The free-body diagram of all forces acting on Bob looks like: A B C D None of the above

A student pulls a 60 Newton sled by applying a force of 20 Newtons. What is the magnitude of the force that the sled exerts on the student? Select one: a. 20 N b. 60 N c. 40 N d. 80 N

Birdman is flying horizontally at a speed of 38 m/s and a height of 71 m. Birdman releases a turd directly above the start of the field. How far from the start of the field should the robot hold the bucket to catch it? Show all work here!

A force F₁ of magnitude 6.10 units acts at the origin in a direction 53.0° above the positive x axis. A second force F₂ of magnitude 5.00 units acts at the origin in the direction of the positive y axis. Find graphically the magnitude and direction of the resultant force F₁ + F₂. magnitude units direction counterclockwise from the +x axis