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Force and acceleration

Please see attachment. 11. What is the weight of a 2.50-kg bag of sand on the surface of the earth? 12. A 2.00-kg projectile is fired at an angle of 20.0 degrees. What is the magnitude of the force exerted on the projectile when it is at the highest position of its trajectory? 13. A 44-kg child steps onto a scale and the s

circular motion explanation

Please see attachment. Thank You your help is greatly needed. 1. A ball moves with a constant speed of 4 m/s around a circle of radius 0.25 m. What is the period of the motion? 2. A racecar is traveling at constant speed around a circular track. What happens to the centripetal acceleration of the car if the speed is doubled

the acceleration of the ladder extension on the firetruck

The firetruck us moving forward at a speed of 35 MPH and is decelerating at a rate of 10ft/sec.^2. Simultaneously, the ladder is being raised and extended. At the instant considered the angle Ø is 30° and is increasing at a rate of 10 degrees/sec . Also at this instant the extension b of the ladder is 5 ft and Vb = 2 feet /

Angular Acceleration Rotational Dynamics

Please see the attached file. 5/139. The sliding collar moves up and down the shaft, causing an oscillation of crank OB. If the velocity of A is not changing as it passes the null position where AB is horizontal and OB is vertical, determine the angular acceleration of OB in that position.

Force: Motion on an incline with friction.

Problem: The incline is 30 degrees with a kinetic friction coefficient of 0.20. Initially the system is not moving. It is given a push uphill at 1m/s and there is a total distance of 1.5m from initial point to the end of the incline. a. Minimum coefficient of friction to keep the system from moving initially b. Whe

Calculating Projectile in Motion: Example Problems

A projectile of mass 20.2 kg is fired at an angle of 65.0 degrees above the horizontal and with a speed of 84.0 m/s. At the highest point of its trajectory the projectile explodes into two fragments with equal mass, one of which falls vertically with zero initial speed. You can ignore air resistance. a) How far from the point

Relative Motion and Energy

See Attachments Please include all FBD and explanations. 1. The launch catapult of an aircraft carrier gives the 7Mg jet airplane gives the airplane a constant acceleration and launches the airplane in a distance of 100 m measured along the angled takeoff ramp. The carrier is moving at a constant speed of 16 m/s. If an ab

Rocket driven car - Expression for acceleration

Please see attachment for full problem description. A rocket-driven car of total mass M loses mass at a constant rate lembda per unit of time at a constant ejection speed V relative to the car. If the total resistance to motion is kv with the speed is v, show that the acceleration of the car along a straight horizontal road i

Parametric Equations : Describing the Motion of a Ball

A baseball pitcher throws a baseball with an initial velocity of 133 feet per second at an angle of 20° to the hoizontal. The ball leaves the pitcher's hand at a height of 5 feet. Find parametric equations that describe the motion of the ball as a function of time. How long is the ball in the air? When is the ball at its maximu

Set of 15 problems on gravitation.

1. Given the perihelion distance, aphelion distance and speed at perihelion of a planet, which of the following cannot be calculated? a) the mass of the start b) the mass of the planet c) the speed of the planet at aphelion d) the period of orbit e)the semimajor axis of the orbit 2. The mass density of a certain planet

force applied to the block and slab system

Please see attached file for full problem description. A 4.40-kg block is placed on top of a 5.50-kg slab. If the slab is held fixed, the block can be made to slip only if a minimum force of 12.0 N is applied to it. The assembly is now placed on a horizontal, frictionless surface, as shown in the diagram. a) What is th

average speed and acceleration

1) If you travel 1 mile AT THE SPEED OF 1000 mi/h, and another mile at the speed of 1 mi/h, what is your average speed? 2) A body with an initial velocity of 8m/s moves with constant acceleration and travels 640m in 40sec. What is its acceleration?

Magnitude of force and acceleration

A 4.44 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=10.7N at an angle theta=22.0degrees above the horizontal, as shown. What is the magnitude of the acceleration of the block when the force is applied? What is the magnitude of the normal force acting on the block when the force

Average Net Force/Acceleration

1. During a circus performance, a 73.0-kg human cannonball is shot out of an 17.7-m-long cannon. If the human cannonball spends 0.812 s in the cannon, determine the average net force exerted on him in the barrel of the cannon. (Assume an the acceleration is constant.) 2. A newly discovered planet has a mass that is 1.45 times

Relativistic Energy and Momentum

1. Given: The charge on the electron is qe = 1.60218 *10 ^-19 C. Given: The mass of the electron is me = 9.10939 * 10 ^-31 kg. What is an electron's momentum, if it is accelerated across a 6 mm potential difference of 220 kV? Answer in units of keV/c. 2. Determine the energy required to accelerate an electron

Electric Force and Coulomb's Law between Two Point Charges

Objects A and B are both positively charged. Both have a mass of 500 g, but A has twice the charge of B. When A and B are placed 50.0 cm apart, B experiences an electric force of 0.810 N. 1) How large is the force on A? 2) What are the charges q_A and q_B? 3) If the objects are released, what is the initial acceleration of

Acceleration and Force/Newton's Laws of Motion

Acceleration & Force : 1. Calculate the average acceleration of a car that changes speed from 0 m/s to 15 m/s in 5 s. 2. Suggest why placing wheels under a heavy box reduces the necessary force required to push it along at a constant speed. 3. Evaluate the change of motion in the following cases in which the forces o

Physics Questions on Impact, Speed, Acceleration

1. In her Mustang, Kelly rounds a curve onto a straight section of country road while traveling at 45 mph, only to find a fully loaded manure spreader completely blocking the road 37 m ahead of her. Startled, she travels at a constant velocity for 0.80 s of reaction time, then hits the brakes and slows with a constant accelerati

Change in momentum and average force

A 1 kg softball is pitched to you at 10 m/s. You hit the ball back along the same path, and at the same speed. A). If the bat was in contact with the ball for .01 seconds, find the magnitude and direction of an average force the bat exerted. B). Find the magnitude of the impulse acting on the ball. C. Find the change in

Linear speed of a bicycle chain and centripetal acceleration

The front and rear sprockets on a bicycle have radii of 9.00 and 5.10 cm, respectively. The angular speed of the front sprocket is 8.00 rad/s. (a) Determine the linear speed (in cm/s) of the chain as it moves between the sprockets and (b) Determine the centripetal acceleration (in cm/s2) of the chain as it passes around t

apparent weight of the person in an elevator

A 75.0 kg person stands on a scale in an elevator. What is the apparent weight in each of the following situations? (a) when the elevator is accelerating upward with an acceleration of 1.80 m/s2 (b) when the elevator is moving upward at a constant speed (c) when the elevator is accelerating downward with an acceleratio

Elementary Differential Equations

64. (The clepsydra, or water clock) A 12 hour water clock is to be designed with the dimensions shaped like the surface obtained by revolving the curve y = f(x) around the y-axis. What should be this curve, and what should be the radius of the circular bottom hole, in order that the water level will fall at the constant rate o

Determine if the disk slips at this instant.

Problem # 9 - The semicircular disk having a mass of 10 kg is rotating at  = 4 rad/s at the instant  = 60 . If the coefficient of static friction at A is  s = 0.5, determine if the disk slips at this instant. See attached file for full problem description.

Force of Friction over a Pulley

1. Two masses are attached with a pulley over an incline which is over a platform. The top of the incline to the ground is 6m. There is one mass on that ramp which is 5.0kg. The other mass which is hanging freely off the ramp is 20.0kg. The force of kinetic friction between the 5.0kg mass and the ramp is .26. The 5.0kg mass is a

Bounce for a moving car

The car with its passengers is traveling along a horizontal road when it suddenly runs onto a new piece of road surface, raised 5.5 cm above the old surface. Assume that this suddenly raises the wheels and the bottom ends of the springs through 5.5 cm before the body of the car begins to move upward. In the ensuing rebound, are

Plane Reversing Course

1. In airplane traveling at 529 km/hr needs to reverse its course. The pilot decides to accomplish this by banking the wings at an angle of 41.0 degrees. a) Find the time needed to reverse course. b) How heavy would a 56 kg passenger feel during the turn? In other words, what would be the magnitude of the total force exerte

Projectile motion with angles

A football is kicked at an angle of 50 degrees and travels a distance of 20 m before hitting the ground. a. What is the initial speed of the ball? b. How long is it in flight? c. How high does it rise?

Force Exerted by rope on crate

A 40.0-kg crate is being lowered by means of a rope. Its downward acceleration is 2.00 m/. What is the force exerted by the rope on the crate? 40.0 N 232 N 312 N 472 N A 40.0-kg crate is being raised by means of a rope. Its upward acceleration is 2.00 m/. What is the force exerted by the rope o