Answer:
v = 10.84 m/s
Explanation:
using the equation of motion:
v^2 = (v0)^2 + 2×a(r - r0)
<em>due to the hammer starting from rest, vo = 0 m/s and a = g , g is the gravitational acceleration.</em>
v^2 = 2×g(r - r0)
v = \sqrt{2×(-9.8)×(4 - 10)}
= 10.84 m/s
therefore, the velocity at r = 4 meters is 10.84 m/s
Answer:
1.1397 Nm
Explanation:
When the palmaris longus muscle in the forearm is flexed, the wrist moves back and forth.
If the muscle generates a force
and
, then the torque is equal to 
we see that r = 2.65 cm = 0.0265 m
therefore
torque = 0.0265 x 49.5
= 1.1397 Nm
The angular acceleration of the blade when it's switched off is (-6800 rev/min) divided by (2.8 sec) = -2,428.6 rev/(min-sec) = -40.5 rev/sec^2 .