(a) At a certain instant, a particle-like object is acted on by a force F = (5.20 N)? – (1.90 N) + (7.80 N) k while the object's velocity is v = - (3.40 m/s)i + (4.50 m/s) k. what is the instantaneous rate at which the force does work on the object? (b) At some other time, the velocity consists of only a y component. unit vector.) the force is unchanged, and the instantaneous power is -12.0 w, what is the velocity of the object just then? (Give your answer without a

(a) At a certain instant, a particle-like object is acted on by a force F = (5.20 N)? – (1.90 N) + (7.80 N) k while the object's velocity is v = - (3.40 m/s)i + (4.50 m/s) k. what is the instantaneous rate at which the force does work on the object? (b) At some other time, the velocity consists of only a y component. unit vector.) the force is unchanged, and the instantaneous power is -12.0 w, what is the velocity of the object just then? (Give your answer without a

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter6: Energy Of A System

Section: Chapter Questions

Problem 8OQ: If the net work done by external forces on a particle is zero, which of the following statements...

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If the net work done by external forces on a particle is zero, which of the following statements about the particle must be true? (a) Its velocity is zero. (b) Its velocity is decreased. (c) Its velocity is unchanged. (d) Its speed is unchanged. (e) More information is needed.
A golf club strikes a 0.062-kg golf ball in order to launch it from the tee. For simplicity, assume that the average net force applied to the ball acts parallel to the ball’s motion, has a magnitude of 6120 N, and is in contact with the ball for a distance of 0.0080 m. With what speed does the ball leave the club?
When a click beetle is upside down on its back, it jumps upward by suddenly arching its back, transferring energy stored in a muscle to mechanical energy.This launching mechanism produces an audible click, giving the beetle its name.Videotape of a certain clickbeetle jump shows that a beetle of mass m = 4.0 * 10-6 kg moved directly upward by 0.77 mm during the launch and then to a maximum height of h= 0.30 m. During the launch, what are the average magnitudes of (a) the external force on the beetle’s back from the floor and (b) the acceleration of the beetle in terms of g?
Assume that the force of a bow on an arrow behaves like the spring force. In aiming the arrow, an archer pulls the drawstring back 62 cm from its rest position and holds it in position with a force of 170 N. If the mass of the arrow is 59 g and the "spring" is massless, what is the speed (in m/s) of the arrow immediately after it leaves the bow?
A sledgehammer of mass m = 1.9 kg falls freely vertically downward from a height of h = 2.5 m at an initial speed of v = 6.5 m/s before striking a partially buried piling. After the blow the piling has moved d = 0.075 m deeper. How much force, in newtons, was applied to the piling? Assume all the energy goes towards driving the piling into the ground, and the force of the sledgehammer is constant over the distance d that the piling is driven into the ground. Note that you can ignore the change in potential energy of the piling itself. Further, because d is so small compared to h, you can also ignore the change in potential energy of the hammer as well as it moves distance d.
If a 1.5 kg object is initially at rest on a frictionless, horizontal surface and subjected to a 14.9 N force in the positive x-direction over a distance of 3.14 meters, what will the object’s final speed be? Assume the answer in in m/s.
Three wooden blocks with masses of 2.0 kg, 12 kg, and 10 kg are attached by a rope and pulley system, asshown. When the 12-kg block is released from rest, it has a speed of 1.0 m/s after moving 1.0 m. Find thecoefficient of kinetic friction between the 12-kg block and the horizontal surface on which it rests. [Answer: µk = 0.56]
A soccer ball with mass 0.460 kgkg is initially moving with speed 2.10 m/sm/s. A soccer player kicks the ball, exerting a constant force of magnitude 38.0 NN in the same direction as the ball's motion. Over what distance must the player's foot be in contact with the ball to increase the ball's speed to 6.00 m/sm/s? Express your answer in meters
Two rigid bodies, A and B, both 1 kg in mass, are connected by a linear spring with a spring constant of 0.2 N/m. Initially, the spring is unstretched and the bodies are at rest. If multiple forces and moments are applied to the two bodies that result in the speed of body A increasing to 10 m/s, the speed of body B increasing to 4 m/s, and the stretch of the spring increasing by 10 m, then -20 Nm of work was done by the spring on the body A, B system. Two rigid bodies, A and B, both 1 kg in mass, are connected by a linear spring with a spring constant of 0.2 N/m. Initially, the spring is unstretched and the bodies are at rest. If multiple forces and moments are applied to the two bodies that result in the speed of body A increasing to 10 m/s, the speed of body B increasing to 4 m/s, and the stretch of the spring increasing by 10 m, then -20 Nm of work was done by the spring on the body A, B system. True False
Hi I am in physics I, and they have the problem: In a baseball game, the 145g ball reaches the batter with a speed of 15.0m/s. The batter hits the ball with a force as shown in exact oppositie direction. The peak force (F max) is 1500N. Find the ball speed right after the hit. It was solved like: J= mvf - mvi area=1/2*b8h J= area = 1500(6)/2 + 1500(2)/2 J=6000 J=6.0 N*s 6.0 N*s = (0.1 +5kg)vf - (0.145kg)(-15) solve for vf vf=26.38 I really don't understand where 0.1 came from. If you can just break down i bit how this is solve that would be great. Thanks!
A man pushing a crate of mass m = 92.0 kg at a speed of v = 0.870 m/s encounters a rough horizontal surface of length ℓ = 0.65 m as in the figure below. If the coefficient of kinetic friction between the crate and rough surface is 0.351 and he exerts a constant horizontal force of 289 N on the crate. A man pushes a crate labeled m, which moves with a velocity vector v to the right, on a horizontal surface. The horizontal surface is textured from the right edge of the crate to a horizontal distance ℓ from the right edge of the crate. (a) Find the magnitude and direction of the net force on the crate while it is on the rough surface. magnitude N direction ---Select--- same as the motion of the crate opposite as the motion of the crate (b) Find the net work done on the crate while it is on the rough surface. J(c) Find the speed of the crate when it reaches the end of the rough surface. m/s
When a 1984 Alfa Romeo Spider sports car accelerates at the maximum possible rate, its motion during the first 20 s is extremely well modeled by the simple equation: v2x =(2P/m)*twhere P=3.6×104 W is the car's power output, m = 1200kg is its mass, and vx is in m/s. That is, the square of the car's velocity increases linearly with time Find a symbolic expression, in terms of P, m, and t, for the car's acceleration at time t.