Given: Force=8000N
displacement= 15 m
W=denotes Work
W= f × d
Substitute Values:
W = 8000 N × 15 m
= 120, 000 Nm
So, the elevator is doing 120, 000 Joule.
( Joule is the SI unit of work)
Answer:
A) L = 0.496 m, B) the movement of the elevator upwards decreases the angular velocity of the pendulum
Explanation:
A) The motion of a simple pendulum is a harmonic motion with angular velocity
w² = g /L
angular velocity and frequency are related
w = 2π f
we substitute
4π² f² = g /L
L =
let's calculate
L = 9.8 / 4 pi² 0.5
L = 0.496 m
B) To see the effect of the elevator acceleration (aₐ), let's use Newton's second law.
At the acceleration from the vertical direction upwards, let's decompose it is a component parallel to the movement and another perpendicular
sin θ = a_parallel / aₐ
a_parallel = aₐ sin θ
this component of the acceleration is in the opposite direction to the movement of the system, so it must be negative
- W sin θ = m (a - a_parallel)
- mg sin θ = m ()
all angles are measured in radians, therefore the angular displacement is
s = L θ
We solve the system for small angles
sin θ = θ
we substitute
- mg θ + m aₐ θ = m L
this is the same equation of the simple pendulum therefore the angular velocity is
w² =
When analyzing this expression, we see that the movement of the elevator upwards decreases the angular velocity of the pendulum
Answer:
(2) Its normal boiling point is above 120°C.
Explanation:
Normal boiling temperature is the temperature at which a substance boils in the atmospheric pressure.
atmosphere pressure is 760 torr.
Clearly, foe this substance increasing the pressure, its B.P. is increases, so at 760 torr, its normal boiling point should be greater than 120° C
(2) Its normal boiling point is above 120°C.
b is not right but thanks it still helped me a lot. i thank you tho