<h2>
Option 3, 216 m is the correct answer.</h2>
Explanation:
We have initial velocity, u = 15 m/s
Time, t = 12 seconds
Final velocity, v = 21 m/s
We have equation of motion v = u + at
Substituting
21 = 15 + a x 12
a = 0.5 m/s²
Now we have equation of motion v² = u² + 2as
21² = 15² + 2 x 0.5 x s
s = 216 m
Displacement = 216 m
Option 3, 216 m is the correct answer.
Average speed = (total distance covered) / (time to cover the distance)
-- Traveling at 40 mph for 1 hour, the distance covered is 40 miles.
-- Traveling at 60 mph for 1 hour, the distance covered is 60 miles.
-- Total distance covered = (40 miles) + (60 miles) = 100 miles
-- Total time = (1 hour) + (1 hour) = 2 hours
-- Average speed = (100 miles) / (2 hours)
<em>Average speed = 50 miles per hour</em>
A water pipe freezes and cracks on a cold night. <em> (D)</em>
There are three physical changes going on in this scenario:
1). The air gets cold and dark at night.
2). The water in the pipe freezes and expands.
3). The pipe cracks.
There are no chemical changes in the description.
Answer:
Maximum force will be 29040 N
Explanation:
We have given mass of the piston m = 1.5 kg
Amplitude A = 10 cm = 0.1 m
Angular speed 
We know that angular speed is given by 

Squaring both side

k = 290400 N/m
Now force is given by 