Answer:
a) 24 J
b) Gravitational Force
c) 45 J
d) 0
e) 6.782m/s
Explanation:
a) m = 3kg
v = 4m/s
h = 1.5m
KE = ?
0.5 * 3 * 16 = 24J
b) Gravitational force
c) F = ma = 3 * 10 = 30N
Work done = Force * distance = 30 * 1.5 = 45J
d) Final Kinetic Energy of the ball is zero because the ball eventually stops moving
e) velocity of ball as it strikes the ground = v
where
v is the velocity as it strikes the ground
u is the initial velocity
a is acceleration
s is the distance
Now since the ball is thrown downwards, a is positive because the velocity of the ball is increasing as the gravitational force acts on it
u = 4m/s
a = 10
s = 1.5
=> 
= 
= 
Answer:
t=7.33 s
Explanation:
According to Newton's second law:
because we don't want the box to slide, the acceleration has to be zero.
we know that:
Now having the acceleration, we can use the following formula.
Answer:
Option A and D
Radius of the sphere, and,
Average net force exerted on the sphere from 0 to 3s
Explanation:
The product of the average net force and the radius will give the torque
T = F x r
The product of torque and time will give the change in angular momentum
T x t = I2w2 - I1w1
Where F is the average force,
r is the radius,
T is the torque,
t is the time (0 to 3sec)
I = moment of inertia of the system
w is the angular speed.
Energy cannot be CREATED or destroyed, just changed or moved.
