initial velocity=0m/s
acceleration=4.2m/s^2
time taken =5s
then final velocity
v=u+at
or, v=0+4.2*5
so final velocity is 21m/s
Answer:
a) about 20.4 meters high
b) about 4.08 seconds
Explanation:
Part a)
To find the maximum height the ball reaches under the action of gravity (g = 9.8 m/s^2) use the equation that connects change in velocity over time with acceleration.
In our case, the initial velocity of the ball as it leaves the hands of the person is Vi = 20 m/s, while thw final velocity of the ball as it reaches its maximum height is zero (0) m/s. Therefore we can solve for the time it takes the ball to reach the top:
Now we use this time in the expression for the distance covered (final position Xf minus initial position Xi) under acceleration:
Part b) Now we use the expression for distance covered under acceleration to find the time it takes for the ball to leave the person's hand and come back to it (notice that Xf-Xi in this case will be zero - same final and initial position)
To solve for "t" in this quadratic equation, we can factor it out as shown:
Therefore there are two possible solutions when each of the two factors equals zero:
1) t= 0 (which is not representative of our case) , and
2) the expression in parenthesis is zero:
<span>Increase the wavelength of the light
</span>
Momentum is a vector quantity. The direction of the momentum vector is the same as the direction of the velocity of the ball. In a previous unit, it was said that the direction of the velocity vector is the same as the direction that an object is moving.
I hope it's help you..
Thanks♥♥
Answer:
towards right so it is -15 degree
Explanation:
Net force in forward direction due to all three is given as
here we know that
Similarly in Y direction we will have
Now the net force on the donkey is given as
Now direction of force is given as
towards right so it is -15 degree