Answer:
the work done by air resistance is 38.5 J
Explanation:
given information:
mass of the ball, m = 0.25 kg
initial speed, = 40 m/s
final speed, = 30 m/s
horizontal distance, x = 120 m
Δh = 20 m
according to conventional energy
W = -
where
is initial energy
is final energy
E = KE + PE
KE is kinetic energy
PE is potential energy
W = -
= mg + - (mg + )
= mg( )+
= m (gΔh + )
= 0.25 ( (9.8) (20) + )
= - 38.5 J
there are different types of power so ill show you all the examples of power.
penguins! so momentum is based on mass and velocity, the advantages is that they have stored mass in the form of like fats to keep them warm however they are built to slide basically so that there is less friction when they travel so sideways their bullet like shape helps increase velocity so they have both mass and considerable velocity!
This question involves the concepts of the equations of motion both in the horizontal motion and the vertical motion.
The rock hits "30.91 m" away from the base of the building.
First, we will calculate the time taken by the rock to reach the ground by applying the second equation of motion in vertical motion:
where,
h = height of the building = 30 m
vi = initial vertical speed = 0 m/s
t = time = ?
g = acceleration due to gravity = 9.81 m/s²
Therefore,
t = 2.47 s
Now, we will calculate the horizontal distance by analyzing horizontal motion. Ignoring the air friction, the horizontal motion will be uniform:
where,
s = horizontal distance = ?
v = horizontal speed = 12.5 m/s
Therefore,
<u>s = 30.91 m</u>
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Learn more about equations of motion here:
brainly.com/question/5955789?referrer=searchResults