I think centripetal force ☺
Answer:
Options d and e
Explanation:
The pendulum which will be set in motion are those which their natural frequency is equal to the frequency of oscillation of the beam.
We can get the length of the pendulums likely to oscillate with the formula;

where g=9.8m/s
ω= 2rad/s to 4rad/sec
when ω= 2rad/sec

L = 2.45m
when ω= 4rad/sec

L = 9.8/16
L=0.6125m
L is between 0.6125m and 2.45m.
This means only pendulum lengths in this range will oscillate.Therefore pendulums with length 0.8m and 1.2m will be strongly set in motion.
Have a great day ahead
Answer:
The car traveled the distance before stopping is 90 m.
Explanation:
Given that,
Mass of automobile = 2000 kg
speed = 30 m/s
Braking force = 10000 N
For, The acceleration is
Using newton's formula

Where, f = force
m= mass
a = acceleration
Put the value of F and m into the formula

Negative sing shows the braking force.
It shows the direction of force is opposite of the motion.


For the distance,
Using third equation of motion

Where, v= final velocity
u = initial velocity
a = acceleration
s = stopping distance of car
Put the value in the equation


Hence, The car traveled the distance before stopping is 90 m.
Assume a maximum stopping acceleration of g/2 where g is acceleration due to gravity.
Answer:
2.99 m/s
Explanation:
Stopping distance, s = 3 ft = 0.914 m
final velocity, v = 0
a = g/2 = 4.9 m/s²
Use third equation of motion:

substitute the values to find the speed of train:
