Answer:
150J
Explanation:
Formula : <u>Work</u><u> </u><u>done</u>
Force x distance
work done = force x distance
Distance should be measured in meters
300÷100=3m
work done = 450 x 3
=150J
Answer:
Explanation:
(b) The initial velocity is added to that due to acceleration by gravity. The velocity is increased linearly by gravity at the rate of 9.8 m/s². The average velocity of the pebble will be its velocity halfway through the 2-second time period.* That is, it will be ...
4 m/s + (9.8 m/s²)(2 s)/2 = 13.8 m/s . . . . average velocity
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(a) The distance covered in 2 seconds at an average velocity of 13.8 m/s is ...
d = vt
d = (13.8 m/s)(2 s) = 27.6 m
The water is about 27.6 m below ground.
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* We have chosen to make use of the fact that the velocity curve is linear, so the average velocity is half the sum of initial and final velocities:
vAvg = (vInit + vFinal)/2 = (vInit + (vInit +at))/2 = vInit +at/2
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If you work this in a straightforward way, you would find distance as the integral of velocity, then find average velocity from the distance and time.

(1) friction is the force resisting the relative motion of solid surfaces , fluid layers and material elements sliding against each other.
(2) gravity is a science fiction .
(3) Resistance ::: is a property of a conductor by which the passage of current is opposed causing electric energy to be transformed into heat .
(4) viscosity is the quantity that describes a fluid.
(5)
consider the velocity towards the pitcher as positive
m = mass of the baseball = 0.145 kg
v₀ = initial velocity of the baseball = - 39 m/s
v = final velocity of the baseball = 52 m/s
t = time of contact = 3 x 10⁻³ sec
F = average force between bat and ball
Using impulse-change in momentum equation
F t = m (v - v₀ )
F (3 x 10⁻³) = (0.145) (52 - (- 39))
F = 4398.33 N