Here are some problems I need help with! Please show ALL the WORK! :) 1. A crane

Question

Here are some problems I need help with! Please show ALL the WORK! :)

1. A crane lifts a block of mass 260kg vertically at an acceleration of 8.5 m/s2 through a height of 1.6m. What is the net force on the block?

Here are the choices for question 1. A=3356N, B=0N, C=4081N, D=21680N, E=None of the above (Which letter is it). Please show all work as to why it is that answer!

2. (Please refer to problem on the image! & SHOW ALL WORK!)

3. In victory, the skater is lifted upward by her teammates with an acceleration of 2.8m/s2. How much force do her teammates exert on her?

4.The skater and her teammates take a victory lap around the rink. How much force do her teammates need to exert to hold her motionless over thier heads?

Explanation / Answer

1) net force = m*accleration = 260*8.5 = 2210 N Answer

2) Max static friction = mu*m*g = 0.7*100 = 70 N

So in first and second case box will not move.

and since in first case force applied is 25 N so friction will also be 25 N. So A will be answer

and max kinetic friction = 0.25*100 = 25 N

So when box move it will exprience 25 N friction force so C and D are answer

Hence final answer is A,C and D

3) forces are equal and opposite

=> if mass of team mate is m

then force = mg + ma = (9.81+2.8)m N Answer

4) Force = mg = 9.81m N Answer

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.