Explanation:
Given that,
Displacement in ice block,
Force exerted by water,
To find,
Work done by the force during the displacement.
Solve,
We know that the product of force and displacement is called work done. It is also equal to the dot product of force and displacement as :
We know that, i.i = j.j = k.k = 1
So, the work done by the force on the block during the displacement is 4181 Joules.
Answer:
15.24 m/s in the downward direction
Explanation:
Given that the initial upward velocity of the ball is 24 m/s.
Assuming that the upward direction is positive.
As gravitational force acts in the downward direction and the direction of acceleration is the same as the direction of force, so the acceleration due to gravity will be negative.
Now, from the equation of motion, when an object is launched with initial velocity u, the final velocity, v, of an object after time t is v=u+at.
Given that u=24 m/s, t=4 seconds, .
So, the final velocity is
m/s
Here, the negative sign means the final velocity is in the downward direction.
Hence, the velocity after 4 seconds is 15.24 m/s in the downward direction.
Answer:
The work done by friction was
Explanation:
Given that,
Mass of car = 1000 kg
Initial speed of car =108 km/h =30 m/s
When the car is stop by brakes.
Then, final speed of car will be zero.
We need to calculate the work done by friction
Using formula of work done
Put the value of m and v
Hence, The work done by friction was