Problema Solution
A front door of a car requires a torque of 50N-m to swing it open. The handle of the door is 0.75m away from the axis where the hinges are attached. What is the minimum force needed to open the door?
Answer provided by our tutors
Take for example, v=u+at you can similarly write ¤=#+wt for rotational. So according to your first problem, ¤=0
#=100
w=-1.5
to find t, i will rearrange the formula as t=(0-100)/-1.5
so t=66.66 seconds
your second problem is also very easy to solve. ¿=r X f
this formula can be simply written as ¿=rf only in this case because we are sure that both the vectors are perpendicular to each other.
¿=50
r=0.75
f=¿/r=66.66N