Hot water<span> seems to </span>freeze faster<span> than </span>cold water<span>, known as the Mpemba effect. The effect was named after the Tanzanian student who in 1963 noticed that </span>hot<span> ice cream mix </span>freezes faster<span> than a </span>cold<span> one. hope this helped</span>
The acceleration of the baseball is:

where

and

are the final and initial speed of the ball, and

is the time interval in which the force acted.
Replacing the numbers, we get

And at this point, we can use Newton's second law F=ma to find the value of the force of the pitching machine:
<u>Answer:</u>
Option (a)
<u>Explanation :</u>
A stage hand starts sliding a large piece of stage scenery originally at rest by pulling it horizontally with a force of 176 N.
Hence Force applied 
Force on piece of scenery 



µk = 
= 
=
=0.36
coefficient of static friction is 0.36
Answer:
(a) the time needs for her to cross the river is 2736.8 s.
(b) the distance takes to reach the other side of the river is 2490.5 m.
Explanation:
given information:
woman's speed, v₁ = 1.9 m/s
the wide of river, s = 5.2 km = 5200 m
river's current, v₂ = 0.91 m/s
(a) How much time does it take her to cross the river?
s = v t
s = the displacement (m)
v = speed (m/s)
t = time (s)
s = v t
t = s/v
= 5200/1.9
= 2736.8 s
(b) How far downstream will the river carry her by the time she reaches the other side of the river?
s = v t
= (0.91) (2736.8)
= 2490.5 m
Speed with which initially car is moving is 21 m/s
Reaction time = 0.50 s
distance traveled in the reaction time d = v t
d = 21 * 0.50 = 10.5 m
deceleration after this time = -10 m/s^2
now the distance traveled by the car after applying bakes



so total distance moved before it stop
d = 22.05 + 10.5 = 32.55 m
so the distance from deer is 35 - 32.55 = 2.45 m
now to find the maximum speed with we can move we will assume that we will just touch the deer when we stop
so our distance after brakes are applied is d = 35 - 10.5 = 24.5 m
again by kinematics



so maximum speed would be 22.1 m/s