Please help with all parts. Thank you A) To push a 50-kg crate up a frictionless

Question

Please help with all parts. Thank you

A) To push a 50-kg crate up a frictionless incline angled at 44° to the horizontal, a worker exerts a force of 484 N parallel to the incline. The crate moves a distance of 2.2 m.
What work is done on the crate by the worker? m/s

What work is done on the crate by the weight of the crate? (use g = 10 m/s2) m

What work is done by the normal force exerted by the floor on the crate?  m

What is the total work done on the crate? m

B) A car moving at speed of 5.0 m/s crashes into an identical car stopped at a light. What is the speed (in m/s) of the wreckage immediately after the collision, assuming the cars stick together

C) The table has a height of 1.25 m, and the initial speed of ball A is vA0=2.9 m/s. What is ball A's speed just before it hits the floor?

D) At what distance from the table's edge will ball A hit the floor?

Explanation / Answer

A)

a) W_workder = F*d*cos(0)

= 484*2.2*1

= 1065 J

b) W_weight = m*g*sin(theta)*d*cos(180)

= -m*g*sin(44)*d

= -50*10*sin(44)*2.2

= -764 J

c) W_normal = N*d*cos(90)

= 0

d) Total workdone = W_worker + W_weight + W_normal

= 1065 - 764 + 0

= 301 J

B) apply conservation of momentum

m*v1 = (m + m)*vf

vf = m*v1/(2*m)

= v1/2

= 5/2

= 2.5 m/s

C) vx = 2.9 m/s

vy = sqrt(2*g*h)

= sqrt(2*9.8*1.25)

= 4.95 m/s

final speed, v = sqrt(vx^2 + vy^2)

= sqrt(2.9^2 + 4.95^2)

= 5.74 m/s

D) let t is the time taken fall down

use, h = (1/2)*g*t^2

t = sqrt(2*h/g)

= sqrt(2*1.25/9.8)

= 0.505 s

horizontal distance travelled before striking the ground,

x = vox*t

= 2.9*0.505

= 1.46 m

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