Answer:
(1) 0.333 Hz
(2) 4 sec
(3) 2 sec, 0.5 Hz
Explanation:
(1) We have given time period of pendulum is 3 sec
So T = 3 sec
Frequency will be equal to 
(2) Frequency of the pendulum is given f = 0.25 Hz
Time period is equal to 
(3) It is given that a pendulum makes 10 back and forth swings in 20 seconds
So time taken to complete 1 back and forth swings = 
So time period T = 2 sec
Frequency will be equal to 
Answer:
The maximum safe speed of the car is 30.82 m/s.
Explanation:
It is given that,
The formula that models the maximum safe speed, v, in miles per hour, at which a car can travel on a curved road with radius of curvature r r, is in feet is given by :
.........(1)
A highway crew measures the radius of curvature at an exit ramp on a highway as 380 feet, r = 380 feet
Put the value of r in equation (1) as :

v = 30.82 m/s
So, the maximum safe speed of the car is 30.82 m/s. Hence, this is the required solution.