If you write down the formula for friction, you will get an answer.
Ff = u * N Where N is a push down force that an object experiences.
u (mu) is a constant and has no units
It may not be accelerating and still experience friction. A is not correct.
Color and Density will not affect the frictional force. B is not so.
Buoyant forces are a different thing altogether. Generally friction has nothing to do with them. C is incorrect.
The last one is your answer. Technically mg should be the answer and not mass, but the second part is correct.
Complete part of Question: What is Jane's (and the vine's) angular speed just before she grabs Tarzan
Answer:
Jane's (and the vine's) angular speed just before she grabs Tarzan, w = 1.267 rad/s
Explanation:
According to the law of energy conservation:
Total change in kinetic energy = Total change in potential energy
Mass of Jane = 60 kg
Mass of the vine = 32 kg
Mass of Tarzan = 72 kg
Height of Tarzan = 5.50 m
Length of the vine = 8.50 m
Jane's change in gravitational potential energy,
Vine's gravitational potential energy,
Vine's Kinetic energy :
Jane's Kinetic energy:
3234 + 862.4 = 2167.5w² + 385.33w²
4096.4 = 2552.83w²
w² = 4096.4/2552.83
w² = 1.605
w = √1.605
w = 1.267 rad/s
When a pendulum is at the midpoint of its oscillation, hanging straight down ...
-- that's the fastest it's going to swing, so its kinetic energy is maximum;
and
-- that's the lowest it's going to get, so its potential energy is minimum.
'c' is your choice.
Easy. answers B. Because 15.00x2=30
E = 300km * 2000J/km = 600000J
The rotational energy is given by:
E = 0.5 * I * ω²
I for a uniform cylinder is given by:
I = 0.5 * m * r²
Resulting equation:
E = 0.25 * m * r² * ω²
Given values:
ω = 430 rev/s = 430 * 2π / s
E = 600000
Solve for r.
