Answer;
=0.43 m/s²
Solution;
There will be the tension in the cable, T, upwards and the weight of the elevator, mg, downwards.
By Newton's second law, the sum of the forces will be equal to mass×acceleration.
Resultant force = m × a
Then T - mg = ma so the tension in the cable is
T = m(g+a)
The cable will break when T = 21,800 N
Solving for a, that happens when
a = 21800/2130 - g
= 10.23 - g (in m/s^2)
If you're using g = 9.8 m/s^2
Then the maximum acceleration allowed is 10.23-9.8 = 0.43 m/s^2
Answer:
The box is moved at constant speed, then the change in kinetic energy is zero.
Explanation:
Let suppose that box moves at constant speed, meaning that its kinetic energy (
), measured in joules, is expressed by the following equation:
(1)
Where:
- Mass, measured in kilograms.
- Speed, measured in meters per second.
If the box moves at constant speed, then we notice that 
, therefore, 
. In a nutshell, if the box is moved at constant speed, then the change in kinetic energy is zero.
There are two torques t1 and t2 on the beam due to the weights, one torque t3 due to the weight of the beam, and one torque t4 due to the string.
You need to figure out t4 to know the tension in the string.
Since the whole thing is not moving t1 + t2 + t3 = t4.
torque t = r * F * sinФ = distance from axis of rotation * force * sin (∡ between r and F)
t1 =3.2 * 44g
t2 = 7 * 49g
t3 = 3.5 * 24g
t4 = t1 + t2 + t3 = 5570,118
The t4 also is given by:
t4 = r * T * sin Ф
r = 7
Ф = 32°
T: tension in the string
T = t4 / (r * sinФ)
T = t4 / (7 * sin(32°))
T = 1501,6 N
Answer:
Increase
Explanation:
because it's increasing up.
Answer:
0.51
Explanation:
m = mass of the book = 3.5 kg
F = force applied by the broom on the book = 21 N
a = acceleration of the book
v₀ = initial speed of the book = 0 m/s
v = final speed of the book = 1.2 m/s
d = distance traveled = 0.74 m
Using the equation
v² = v₀² + 2 a d
1.2² = 0² + 2 a (0.74)
a = 0.973 m/s²
f = kinetic frictional force
Force equation for the motion of the book is given as
F - f = ma
21 - f = (3.5) (0.973)
f = 17.6 N
μ = Coefficient of kinetic friction
Kinetic frictional force is given as
f = μ mg
17.6 = μ (3.5 x 9.8)
μ = 0.51
