Are you sure it’s mechanical energy? I haven’t taken a physics class in a while but mechanical energy doesn’t sound right.
Explanation:
Given data
velocity v= 25m/s
The time it takes to put on brake t= 0.3s
the distance covered when the brake was put on is
v=s/t
s= v*t
s= 25*0.3s
s= 7.5m
hence the distance covered is 7.5m
Also the rate of decrease in aceleration is 5m/s^2
we can also calculate the distance covered at this rate
v^2=u^2+2as
25^2= 0+2*5*s
625=10s
divide both sides by 10
s=625/10
s= 62.5m
The total distance covered between putting on the brakes and decelareation is 7.5+62.5= 70m
Given that the tree is 75m ahead, the car would not hit the tree
Explanation:
It is given that,
Speed of the baseball, u = 44 m/s
Speed of the baseball, v = 53 m/s
Mass of the ball, m = 145 g = 0.145 kg
Time of contact between the ball and the bat, t = 2.2 ms = 0.0022 s



F₁ = 2900 N...........(1)



F₂ = 3493.18 N.........(2)
In average vector form force is given by :



Hence, this is the required solution.
Answer:
W= 4.89 KJ
Explanation:
Lets take
temperature of hot water T₁ = 100⁰C
T₁ = 373 K
Temperature of cold ice T₂= 0⁰C
T₂ = 273 K
The latent heat of ice LH= 334 KJ
The heat rejected by the engine Q= m .LH
Q₂= 0.04 x 334
Q₂= 13.36 KJ
Heat gain by engine = Q₁
For Carnot engine


Q₁ = 18.25 KJ
The work W= Q₁ - Q₂
W= 18.25 - 13.36 KJ
W= 4.89 KJ