Answer:
Friction force always acts tangent to the surface at points of contact. Friction force acts opposite to the direction of motion.
Explanation:
The formula for the period of the pendulum is

where L is the pendulum's length and g the gravitational acceleration.
Labeling with E the Earth and with M Mars, we can write the period of the pendulum on Earth as

and the period of the pendulum on Mars as

if we calculate the ratio, we get

but we know that the gravitational acceleration on Mars is 0.37 times the gravitational acceleration on Earth:

Substituting into the formula, we find

And so, the period of the pendulum on Mars is
Answer:
I chose c because it is the greater slope at point c
Answer:
a) 30.82 m/s
b) 183.33 Hz
Explanation:
a)
V = speed of the sound = 339 m/s
v = speed of the train = ?
f' = observed frequency by the observer = 220 Hz
f = actual frequency of the observer = 200 Hz
using the equation


v = 30.82 m/s
b)
V = speed of the sound = 339 m/s
v = speed of the train = 30.82 m/s
f'' = observed frequency by the observer as train moves away = ?
f = actual frequency of the observer = 200 Hz
using the equation


f'' = 183.33 Hz
Hello!
Use the <u>second law of Newton:</u>
F = ma
Replacing:
F = 40 kg * 30 m/s^2
Resolving:
F = 1200 N
The force is <u>1200 Newtons.</u>