Answer:
a)
125.6 rad/s
b)
25.12 rad/s²
Explanation:
a)
t = time required by the fan to get up to final operating speed = 5 sec
w = final operating rotational speed = 1200 rpm
we know that :
1 revolution = 2π rad
1 min = 60 sec
w = 
w = 
w = 125.6 rad/s
b)
w₀ = initial angular speed = 0 rad/s
α = angular acceleration
using the equation
w = w₀ + α t
125.6 = 0 + α (5)
α = 25.12 rad/s²
Answer:
The first
Explanation:
Cause it will continue in motion till another force is applied
Number 5 is A
number 6 is D
This happens in basketball. It is known as "jump ball".
(a) The force exerted by the electric field on the plastic sphere is equal to
where
is the charge of the sphere and E is the strength of the electric field. This force should balance the weight of the sphere:
where m is the mass of the sphere and g is the gravitational acceleration.
Since the two forces must be equal, we have:
and so we find the intensity of the electric field
(b) Now let's find the direction of the field. The electric force must balance the weight of the sphere, which is directed downward, so the electric force should be directed upward. Since the charge is negative, the force is opposite to the electric field direction, and so the direction of the electric field is downward.
