First, we must find the vertical distance traveled upwards by the ball due to the throw. For this, we will use the formula:
2as = v² - u²
Because the final velocity v is 0 in such cases
s = -u²/2a; because both u and a are downwards, the negative sign cancels
s = 14.5² / 2*9.81
s = 10.72 meters
Next, to find the time taken to reach the ground, we need the height above the ground. This is:
45 + 10.72 = 55.72 m
We will use the formula
s = ut + 0.5at²
to find the time taken with the initial velocity u = 0.
55.72 = 0.5 * 9.81 * t²
t = 3.37 seconds
Answer:
The tension in the string is quadrupled i.e. increased by a factor of 4.
Explanation:
The tension in the string is the centripetal force. This force is given by
m is the mass, v is the velocity and r is the radius.
It follows that 
, provided m and r are constant.
When v is doubled, the new force, 
, is
Hence, the tension in the string is quadrupled.
Answer:
Fuel cells have a higher efficiency than diesel or gas engines.
Most fuel cells operate silently, compared to internal combustion engines.
Fuel cells can eliminate pollution caused by burning fossil fuels.
Answer:
Explanation:
Given that
Radius =r
Electric filed =E
Q=Charge on the ring
The electric filed at distance x given as
For maximum condition
For maximum condition
At the electric field will be maximum.
