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Body mass problem

The body mass index, I,can be used to determine an individualds risk for heart disease I=700W/h squared height is 71 inches tall. w=weight h=height What weights will keep the body mass between 21 and 32? Body mass index will fall between 21 and 32 for the set of all weights such that x<W<y round to the nearest t

Determining force and coefficient of friction

You pull your 18 kg suitcase at constant speed on a horizontal floor by exerting a 41 N force on the handle, which makes an angle θ with the horizontal. The force of friction on the suitcase is 28 N. What is the normal force on the suitcase? What is the coefficient of friction?

A car travels around a curve of radius R=100m at a constant speed of 30m/s

A car travels around a curve of radius R=100m at a constant speed of 30m/s: (a) What is the centripetal acceleration of the car? (b) If the curve is flat, and we can assume friction, draw the free body diagram for the car (show the coordinate system you choose). (c) Determine the coefficient of friction required to ke

Free Body Diagram & Minimal Force for a Block

See attached file. Provide a stepwise solution. a) Draw the free body diagram for the block. b) What is the minimum Force with which you can push the block and have it move? Fmin=____________ c) You push the block with the Force determined in part (b) and it begins to move. What will the acceleration of the bl

A Question and Solution Around Centripetal Force

A car wheel of radius r rolls without slipping at a constant translational acceleration a. At one instant, the velocity of the axel is v. What net force acts on a small pebble of mass M stuck to the edge of the wheel along the X axis. Repeat for along y axis.

Physics: Acceleration problems

14. An automobile traveling on a straight, level road at 14 m/s speeds up to 25 m/s in 30 seconds. What was the magnitude of the auto's acceleration? 15. Two opposite forces of 6.0 N and 4.0 N act on a 2.0 kg object. What is its acceleration? 16. An automobile with a mass of 100 kg is moving north on a level highway with a

Finding the Force, Mass and Acceleration

1. A horizontal force of 7.2 N acting on a 1.0 kg object initially at rest moves it through a parallel distance of 2.5 m. How much work is done on the object? 2. A student with a mass of 71 kg climbs a flight of stairs 5.0 m high in 10s. Calculate the power expended by the student. 3. A box of mass 5.0 kg is pulled vertica

Acceleration, mass, force, constant speed, velocity, magnitude

A net force of 135N is applied to a certain object. As a result, the object accelerates with an acceleration of 24.0ms^2. What is the mass of the object? A 3.0kg and a 5.0kg box rest side-by-side on a smooth, level floor. A horizontal force of 32N is applied to the 5.0kg pushing it against the 3.0kg box, and, as a result, bot

Force exerted on a baseball by a bat

The force exerted on a 0.140 kg baseball by a bat changes from 0.0 N to 1.0 X 10^4 N over 0.0010 s, then drops back to zero in the same amount of time. The baseball was going toward the bat at 23 m/s. (a) Draw a graph of force versus time. What is the average force exerted on the ball by the bat? (b) What is the accelerati

Magnitude of acceleration and direction of acceleration of a par

An 9.00 kg point mass and a 12.0 kg point mass are held in place 50.0 cm apart. A particle of mass (m) is released from a point between the two masses 20.0 cm from the 9.00 kg mass along the line connecting the two fixed masses. a) Find the magnitude of the acceleration of the particle. (in m/s^2) b) Find the direction of

Physics force and friction: Acceleration, tensions,

** Please see the attached file for the figures ** 4. A 10.0 kg box is attached to a 7.00 kg box which rests on a 30° incline. The coefficient of kinetic friction between each box and the surface is 0.10. Find a)the rate of acceleration of the system and b) the tensions in the

Acceleration of Box: Maximum Angle of Inclination

1. A box of mass 5.0 kg is pulled vertically upwards by a force of 68 N applied to a rope attached to the box. Find a) the acceleration of the box and b) the vertical velocity of the box after 2 seconds. 2. A frictionless ramp 135 m long is to be built for a ski jump. If a skier starting from rest at the top is to have a spee

Magnitude of acceleration and tension, speed of block

In the figure shown, the coefficient of kinetic friction between the block and the incline is 0.29. Disregard any pulley mass or friction in the pulley. a) What is the magnitude of the acceleration on the suspended block as it falls? b) What is the magnitude of the tension acting on the suspended block? c) What is the speed

Lifting a Boulder from a quarry with constant acceleration

A 730-kg boulder is raised from a quarry 123 m deep by a long uniform chain having a mass of 560 kg . This chain is of uniform strength, but at any point it can support a maximum tension no greater than 3.00 times its weight without breaking. A) What is the maximum acceleration the boulder can have and still get out of the qu

Tension in a rope with hanging masses

See the attached file. A superhero and his sidekick are hanging motionless from a rope. The superhero's mass is 90.0kg, while the sidekick's mass is 55.0kg. The mass of the rope is negligible. a. Find the tension in the rope above the superhero. b. Find the tension in the rope above the sidekick

Net Force and acceleration in two cases

Two forces applied to the object with mass m = 5 kg. One force is ... N, another force is ... N (assign your own numbers). Calculate Net Force and acceleration in two cases: 1. both forces applied in the same direction, from left to right ( â?' â?') 2. forces applied in the opposite directions, one to the left, ano

Particle Gravity and Centripetal Acceleration on Blood & a Car

Please see the attachment for questions along with mentioned drawings. 7. The drawing shows three particles far away from any other objects and located on a straight line. The masses of these particles are mA = 363 kg, mB = 517 kg, and mC =154 kg. Find the magnitude and direction of the net gravitational force acting on each

Final velocity in terms of masses and initial height

We are conducting an experiment with two different masses. We have a car on a track tied to a weight that is off of a table rounded by a pulley. When we let go of the car, the weight falls to the ground and the car accelerates toward to the pulley. Derive an equation for final velocity in terms of masses and initial height.

Test rocket is launched vertically from the launch pad

A 2530-kg test rocket is launched vertically from the launch pad. Its fuel (of negligible mass) provides a thrust force so that its vertical velocity as a function of time is given by v(t) = At + Bt^2 , where A and B are constants and time is measured from the instant the fuel is ignited. At the instant of ignition, the rocket h

Moving Tension of load of bricks when rope is passing over a pulley

See attached figure. A load of bricks with mass m1 = 14.2 kg hangs from one end of a rope that passes over a small, frictionless pulley. A counterweight of mass m2= 29.0 kg is suspended from the other end of the rope, as shown in the figure. The system is released from rest. A) What is the magnitude of the upward accele

Kinematics: 8 practice problems

1. A car traveling at a constant speed of 30 m/s passes a police car at rest. The policeman starts to move at the moment the speeder passes his car and accelerates at a constant rate of 3.0 m/s2 until he pulls even with the speeding care. Find a) the time required for the policeman to catch the speeder and b) the distance trave

Weight in an elevator

The weight of a book was measured using a scale. The scale showed 15N. Next, the book and the scale were placed in an elevator that does not show the floor number. When the elevator started moving, the reading of the scale has changed, but later was reading 15N again. Using the fact that the scale shows the same value in the ele

Velocity Components Magnitudes

A dog running in an open field has components of velocity v(x) = 2.2 m/s and v(y)= -1.3 m/s at time t1 = 11.7 seconds . For the time interval from t1 = 11.7 seconds to t2 = 24.1 seconds , the average acceleration of the dog has a magnitude 0.39 m/s^2 and direction 30.0 degrees measured from the positive x-axis toward the posi

Speed of the Moon Lander

A lunar lander is making its descent to Moon Base I. The lander descends slowly under the retro-thrust of its descent engine. The engine is cut off when the lander is 5.0 m above the surface and has a downward speed of 0.80 m/s . With the engine off, the lander is in free fall. What is the speed of the lander just before it

Acceleration Test Data

According to recent test data, an automobile travels 0.250 miles in 19.9 seconds , starting from rest. The same car, when braking from 60.0 mi/h on dry pavement, stops in 146 ft. Assume constant acceleration in each part of the motion, but not necessarily the same acceleration when slowing down as when speeding up. 1) what

Finding Mass of Block Hanging from Ceiling

A block is hanging from the ceiling by a single wire. When a horizontal force of 12 N is applies on the block, the wire makes an angle of 20 degrees with the vertical. What is the mass of the block? a. 0.44 kg b. 1.2 kg c. 1.3 kg d. 3.4 kg e. 3.6 kg See attachment for image.