Question

Jack and Zack are standing on a crate at rest on a frictionless horizontal surface. Jack...

Jack and Zack are standing on a crate at rest on a frictionless horizontal surface. Jack has a mass of 70 kg, Zack has a mass of 45 kg, and the crate has a mass of 15 kg. In what follows, we will see that both jump of the crate. You may assume that they push themselves off with a speed of 4 m/s relative to the crate and in a direction that is essentially horizontal.

a) what is the final speed of the crate if Jack and Zack jump simultaneously, in the same direction?

b) what is the final speed of the crate if Jack and Zack jump simultaneously, in opposite directions?

c)what is the final speed of the crate if Jack jumps first and Zack jumps a few seconds later, in the opposite direction as Jack?

Science   Physics   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
If a crate of mass 5 kg is shot across a flat, frictionless surface with initial...
If a crate of mass 5 kg is shot across a flat, frictionless surface with initial speed of 10 m/s towards a 0.25 m long region with a kinetic coefficient of friction equaling 0.10 , after passing through this region, it collides elastically with a second crate. The second crate has a mass of 0.5 kg. The second crate slides up a frictionless ramp 30 degrees off the horizontal. How high off the ground does the second crate travel before...
A person with mass mp=80 kg is standing at rest on a horizontal, frictionless surface holding...
A person with mass mp=80 kg is standing at rest on a horizontal, frictionless surface holding a ball of wet clay with mass mg=10 kg . In front of the person is a large block with mass M=20 kg at rest next to a spring with stiffness k=100 N/m . The person throws the ball horizontally, it sticks to the block, and then ball and block slide and compress the spring a distance 1=0.75 m away from equilibrium before the...
A 110-kg crate, starting from rest, is pulled across a floor with a constant horizontal force...
A 110-kg crate, starting from rest, is pulled across a floor with a constant horizontal force of 380 N . For the first 14 m the floor is frictionless, and for the next 14 m the coefficient of friction is 0.35. What is the final speed of the crate?
a man (mass=7- kg) and a woman (mass=60kg) are standing at rest on a frictionless surface...
a man (mass=7- kg) and a woman (mass=60kg) are standing at rest on a frictionless surface holding opposite ends of the same rope. Then, the man pulls on the rope so that there is a tension in the rope. If the tension in the rope is 100 N, what is the acceleration of the center of mass of the man-woman system?
A 91 kg crate, starting from rest, is pulled across a floor with a constant horizontal...
A 91 kg crate, starting from rest, is pulled across a floor with a constant horizontal force of 400 N . For the first 15 m the floor is frictionless, and for the next 15 m the coefficient of friction is 0.20. What is the final speed of the crate? Express your answer using two significant figures.
A 17.6-kg crate starts at rest at the top of a 60.0° incline. The coefficients of...
A 17.6-kg crate starts at rest at the top of a 60.0° incline. The coefficients of friction are μs = 0.400 and μk = 0.300. The crate is connected to a hanging 8.00-kg box by an ideal rope and pulley. a) How long does it take the crate to slide 2.00 m down the incline? ( in seconds) b)To push the crate back up the incline at constant speed, with what force should you push on the crate (parallel to...
A 1.75 kg object is initially at rest on a horizontal frictionless surface and is attached...
A 1.75 kg object is initially at rest on a horizontal frictionless surface and is attached to an initially unstretched spring with a force constant of 50 N/m and negligible mass. A constant horizontal force of 338.75 N is applied to the object. Determine the following when the object has slide a distance 0.75 m: the work done by the applied force  J, the energy stored in the spring  J, the object's final kinetic energy  J, and the object's final speed  m/s.
3. A ball of mass 2.00 kg, resting on a horizontal frictionless surface, gets hit by...
3. A ball of mass 2.00 kg, resting on a horizontal frictionless surface, gets hit by another ball of mass 1.50 kg moving in the +x-direction with a speed 4.00 m/s. After the collision, the 1.50 kg ball has a speed of 2.00 m/s at an angle 60.0° counterclockwise from the +x-direction. a) Find the velocity of the 2.00 kg ball just after the collision. Express your answer in vector form. b) Compute the percent of kinetic energy lost in...
A wooden block is at rest on a frictionless horizontal surface and is connected to a...
A wooden block is at rest on a frictionless horizontal surface and is connected to a spring (k =150 N/m). The mass of the wooden block is 0.10 kg. A bullet (mass 0.012 kg) and velocity 270 m/s is fired horizontally into the wooden block. After collision the bullet stays in the block. (a) Find the speed of the bullet-block system right after the collision. (b) If the bullet-block system compresses the spring by a maximum of d. Find d
A 132 lb. (60 kg) person does a standing vertical jump. Starting from rest, she jumps...
A 132 lb. (60 kg) person does a standing vertical jump. Starting from rest, she jumps vertically and reaches 70 cm (= 0.7m). The push-off phase takes 0.5 seconds. After being airborne, the landing takes 0.5 seconds before she comes to rest. e. What is her vertical velocity when she becomes airborne? When she lands? f. How much mechanical work did the leg muscles produce during the push-off? g. How much power did the leg muscles generate during the push...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT