Physics help!!, please write out each steps Thank you. A 550 N student \"stands
ID: 1485287 • Letter: P
Question
Physics help!!, please write out each steps Thank you.
A 550 N student "stands still" on a bathroom scale inside an elevator. Predict the bathroom scale reading in each of the following cases. The elevator and the student are at rest; The elevator is traveling upwards or downwards at a constant 2.0 m/s; The elevator is traveling upwards and speeding up at 1.0 m/s^2; The elevator is traveling downwards and speeding up at 1.0 m/s^2; The elevator is traveling upwards and slowing down at 1.0 m/s^2; The elevator is traveling downwards and slowing down at 1.0 m/s^2. The elevator gets stuck between floors for 5 minutes and the student decides to get some exercise by doing deep knee bends, while still standing on the scale. What happens to the scale reading during each phase of a single, complete deep knee bend? Try it at home!Explanation / Answer
a)
R = mg = 550 N
b)
upwards
R - mg = ma
here speed is constant
a = 0
R = mg = 550 N
downwards
mg - R = ma
here speed is constant
a = 0
R = mg = 550 N
c)
upwards
R- mg = m*a
R = mg + ma
R = mg*(1+a/g) = 550*(1+1/9.8) = 606.12 N
d)
down wards
mg - R = ma
R = mg - ma
R = mg*(1-a/g)
R = 550*(1-1/9.8)
R = 493.87 N
+++++++++++++++
e)
upwards
R- mg = m*a
R = mg + ma
R = mg*(1+a/g)
a = -1
R= 550*(1-1/9.8) = 493.87 N
f )
down wards
mg - R = ma
R = mg - ma
R = mg*(1-a/g)
a = -1
R = 550*(1+1/9.8)
R = 606.12 N