Density = mass / volume = 7/14 = 0.5!g/cm^3
Answer:
11.28 N toward the center of the track
Explanation:
Centripetal force: This is the force that tend to draw a body close to the center of a circle, during circular motion.
The formula for centripetal force is given as,
F = mv²/r................................ Equation 1
Where F = force, m = mass of the toy car, v = velocity, r = radius
Given: m = 108 g = 0.108 kg, v = 7.75 m/s, r = 57.5 cm = 0.575 m
Substitute into equation 1
F = 0.108(7.75²)/0.575
F = 11.28 N
Hence the magnitude and direction of the force = 11.28 N toward the center of the track
Answer:
c. V = 2 m/s
Explanation:
Using the conservation of energy:

so:
Mgh = 
where M is the mass, g the gravity, h the altitude, I the moment of inertia of the pulley, W the angular velocity of the pulley and V the velocity of the mass.
Also we know that:
V = WR
Where R is the radius of the disk, so:
W = V/R
Also, the moment of inertia of the disk is equal to:
I = 
I = 
I = 10 kg*m^2
so, we can write the initial equation as:
Mgh = 
Replacing the data:
(5kg)(9.8)(0.3m) = 
solving for V:
(5kg)(9.8)(0.3m) = 
V = 2 m/s