Answer:
0.75 g/cm^3
Explanation:
The formula for density:

Where m is the mass and V is the volume.
So, we can substitute values for m and V:

Therefore, the density is 0.75 g/cm^3 (watch the units!)
<span>The moment of inertia of the large sphere will be twice that of the smaller sphere.
The formula for the moment of inertia for a solid sphere is:
I = (2/5)mr^2
where
I = moment of inertia
m = mass
r = radius
Since both spheres have the same diameter, they also have the same radius, so the only change is their mass. And the moment of inertia is directly proportional to their mass as shown by the above formula. So the sphere with twice the mass will have twice the moment of inertia, or 2 times.</span>
<span>Answer: Force = 81.6 N
Explanation:
According to Newton's Second law:
F = ma --- (1)
Where F = Force = ?
m = Mass = 68 kg
a = Acceleration = 1.2 m/s^2
Plug in the values in (1):
(1) => F = 68 * 1.2
F = 81.6 N (The force needed to accelerate the skier at a rate of 1.2 m/s^2)</span>
Answer:


Explanation:
if

and g=9.81 m/s2=32.16 ft/s2
and
W=m*g
we can just replace de mass and gravity and we have


Answer:
(A) 11 m/s
(B) 1.3 m
Explanation:
Horizontal range, R = 9.6 m
Angle of projection, theta = 28 degree
(A)
Use the formula of horizontal range
R = u^2 Sin 2 theta / g
u^2 = R g / Sin 2 theta
u^2 = 9.6 × 9.8 / Sin ( 2 × 28)
u = 10.65 m/s
u = 11 m/s
(B)
Use the formula for maximum height
H = u^2 Sin ^2 theta / 2g
H =
10.65 × 10.65 × Sin^2 (28) / ( 2 × 9.8)
H = 1.275 m
H = 1 .3 m