Answer:
786.6 N
Explanation:
mass of car, m = 912 kg
initial velocity of car, u = 31.5 m/s
final velocity of car, v = 24.6 m/ s
time, t = 8 s
Let a be the acceleration of the car
Use first equation of motion
v = u + a t
24.6 = 31.5 + a x 8
a = - 0.8625 m/s^2
Force, F = mass x acceleration
F = 912 x 0.8625
F = 786.6 N
Thus, the force on the car is 786.6 N.
Answer:
20 mA
Explanation:
We have given that the transformer convert 120 V to 12 V means it is a step down transformer
The turn ratio of the transformer is given as
here
is primary voltage and
is secondary voltage
As the voltage decreases from primary to secondary so current will increase from primary to secondary
We have given output current that is secondary current so primary that is input current will be less
So input current
The value of the force, F₀, at equilibrium is equal to the horizontal
component of the tension in string 2.
Response:
- The value of F₀ so that string 1 remains vertical is approximately <u>0.377·M·g</u>
<h3>How can the equilibrium of forces be used to find the value of F₀?</h3>
Given:
The weight of the rod = The sum of the vertical forces in the strings
Therefore;
M·g = T₂·cos(37°) + T₁
The weight of the rod is at the middle.
Taking moment about point (2) gives;
M·g × L = T₁ × 2·L
Therefore;

Which gives;


F₀ = T₂·sin(37°)
Which gives;

<u />
Learn more about equilibrium of forces here:
brainly.com/question/6995192
Complete Question
A certain refrigerator, operating between temperatures of -8.00°C and +23.2°C, can be approximated as a Carnot refrigerator.
What is the refrigerator's coefficient of performance? COP
(b) What If? What would be the coefficient of performance if the refrigerator (operating between the same temperatures) was instead used as a heat pump? COP
Answer:
a

b
Explanation:
From the question we are told that
The lower operation temperature of refrigerator is
The upper operation temperature of the refrigerator is 
Generally the refrigerators coefficient of performance is mathematically represented as

=> 
=> 
Generally if a refrigerator (operating between the same temperatures) was instead used as a heat pump , the coefficient of performance is mathematically represented as
=>
=>
Answer:
t = 0.319 s
Explanation:
With the sudden movement of the athlete a pulse is formed that takes time to move along the rope, the speed of the rope is given by
v = √T/λ
Linear density is
λ = m / L
λ = 4/20
λ = 0.2 kg / m
The tension in the rope is equal to the athlete's weight, suppose it has a mass of m = 80 kg
T = W = mg
T = 80 9.8
T = 784 N
The pulse rate is
v = √(784 / 0.2)
v = 62.6 m / s
The time it takes to reach the hook can be searched with kinematics
v = x / t
t = x / v
t = 20 / 62.6
t = 0.319 s