#82
here we know that
acceleration = 2 m/s/s
time = 5 s
initial speed = 4 m/s
now we can use kinematics to find the final speed



So correct answer will be option D)
#83
here we know that
acceleration = 3 m/s/s
time = 4 s
initial speed = 5 m/s
now we can use kinematics to find the final speed



So correct answer will be option C)
#84
here we know that
acceleration = 7 m/s/s
time = 3 s
initial speed = 8 m/s
now we can use kinematics to find the final speed



So correct answer will be option C)
v^2 = v0^2 +2ad
v^2 = 22^2 + 2*3.78*45 = 824.2
v= √824.2 = 28.7 m/s
Answer:
v = 12.12 m/s
Explanation:
It is given that,
Radius of circle, r = 30 m
The coefficient friction between tires and road is 0.5,
The centripetal force is balanced by the force of friction such that,
v = 12.12 m/s
So, the maximum speed with which this car can round this curve is 12.12 m/s. Hence, this is the required solution.
Work done by a given force is given by

here on sled two forces will do work
1. Applied force by Max
2. Frictional force due to ground
Now by force diagram of sled we can see the angle of force and displacement
work done by Max = 

Now similarly work done by frictional force



Now total work done on sled

