Distance traveled by him = circumference of that circular path = 2πr = 2π(3.5)
= 7π = 7×3.14 = 21.98 m
time = 8.9 s [ Given ]
Now, Average speed = distance / time
s = 21.98 / 8.9
s = 2.46 m/s
Hope this helps!
I assume the 100 N force is a pulling force directed up the incline.
The net forces on the block acting parallel and perpendicular to the incline are
∑ F[para] = 100 N - F[friction] = 0
∑ F[perp] = F[normal] - mg cos(30°) = 0
The friction in this case is the maximum static friction - the block is held at rest by static friction, and a minimum 100 N force is required to get the block to start sliding up the incline.
Then
F[friction] = 100 N
F[normal] = mg cos(30°) = (10 kg) (9.8 m/s²) cos(30°) ≈ 84.9 N
If µ is the coefficient of static friction, then
F[friction] = µ F[normal]
⇒ µ = (100 N) / (84.9 N) ≈ 1.2
Answer:
4 hertz
Explanation:
The defination of freqyency = the total no of cycle made by a wave in one second .
so,
cycle or vibrations=60
tame taken = 15
now,
frequency = no. of cycle / time taken
= 60/15
=4 hertz
hence, the its frequency = 4hertz