A ball thrown downward with an initial velocity of 20m/s.what will be itsvelocity after 5s
To find the velocity of a ball thrown downward after 5 seconds, we need to consider the effects of gravity.
When an object is thrown downward, its initial velocity will be negative, as the velocity is opposite to the direction of motion. In this case, the initial velocity is given as -20 m/s.
Assuming there is no air resistance, the acceleration due to gravity is approximately -9.8 m/s² (negative because it acts downward).
To find the velocity after 5 seconds, we can use the equation of motion:
vf = vi + at
Where:
- vf is the final velocity
- vi is the initial velocity
- a is the acceleration
- t is the time
Substituting the given values:
vf = -20 m/s + (-9.8 m/s²) * 5s
= -20 m/s - 49 m/s
= -69 m/s
Therefore, the velocity of the ball after 5 seconds will be -69 m/s. Note that the negative sign indicates the downward direction.