Answer:
A. kinetic energy
B. angular velocity
E. angular position
Explanation:
The quantities that cannot be constant if a constant net torque is exerted on an objecta are:
A. Kinetic energy. If a torque is applied, the linear or angular speed will be changing at a rate proportional to the torque, so the kinetic energy will change too.
B. Angular velocity. It will change at a rate equal to the torque.
C. Angular position. If the angular velocity changes, the angular position will change.
Answer:
t_total = 23.757 s
Explanation:
This is a kinematics exercise.
Let's start by calculating the distance and has to reach the limit speed of
v = 18.8 m / s
v = v₀ + a t₁
the elevator starts with zero speed
v = a t₁
t₁ = v / a
t₁ = 18.8 / 2.40
t₁ = 7.833 s
in this time he runs
y₁ = v₀ t₁ + ½ a t₁²
y₁ = ½ a t₁²
y₁ = ½ 2.40 7.833²
y₁ = 73.627 m
This is the time and distance traveled until reaching the maximum speed, which will be constant throughout the rest of the trip.
x_total = x₁ + x₂
x₂ = x_total - x₁
x₂ = 373 - 73,627
x₂ = 299.373 m
this distance travels at constant speed,
v = x₂ / t₂
t₂ = x₂ / v
t₂ = 299.373 / 18.8
t₂ = 15.92 s
therefore the total travel time is
t_total = t₁ + t₂
t_total = 7.833 + 15.92
t_total = 23.757 s
To solve this problem we need to use the proportional relationships between density, mass and volume, together with Newton's second law.
The force can be described as
Where,
m = Mass
g = Gravitational acceleration
At the same time the Density can be defined as
Where,
m = mass
V = Volume
Replacing the value of the mass at the equation of Force we have,
Since the difference between the two forces gives us the total Force then we have to
Where
Force of the water
= Force of plastic
Therefore with the values for this force we have,
Therefore the tension in the thread is 16.412N
Answer:
Angular acceleration is defined as the rate of change of angular velocity of a body.
consider the attached figure as shown
It rotates with an angular velocity 
An point inside the object rotates along the path as indicated thus turning by an angle 
in time 't'
Thus we have
physically angular acceleration can be understood as the rate at which the angular speed of any object is changing with time.
