1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Rudiy27
2 years ago
10

A pendulum of length L=36.1 cm and mass m=168 g is released from rest when the cord makes an angle of 65.4 degrees with the vert

ical.
(a) How far does the mass fall (y-displacement) before reaching its lowest point?
(b) How much work is done by gravity as it falls to its lowest point?
(c) How much work is done by the string tension as it falls to its lowest point?
Physics
1 answer:
pychu [463]2 years ago
5 0

(a) -0.211 m

At the beginning the mass is displaced such that the length of the pendulum is L = 36.1 cm and the angle with the vertical is

\theta=65.4^{\circ}

The projection of the length of the pendulum along the vertical direction is

L_y = L cos \theta = (36.1 cm)(cos 65.4^{\circ})=15.0 cm

the full length of the pendulum when the mass is at the lowest position is

L = 36.1 cm

So the y-displacement of the mass is

\Delta y = 15.0 cm - 36.1 cm = -21.1 cm = -0.211 m

(b) 0.347 J

The work done by gravity is equal to the decrease in gravitational potential energy of the mass, which is equal to

\Delta U = mg \Delta y

where we have

m = 168 g = 0.168 kg is the mass of the pendulum

g = 9.8 m/s^2 is the acceleration due to gravity

\Delta y = 0.211 m is the vertical displacement of the pendulum

So, the work done by gravity is

W=(0.168 kg)(9.8 m/s^2)(0.211 m)=0.347 J

And the sign is positive, since the force of gravity (downward) is in the same direction as the vertical displacement of the mass.

(c) Zero

The work done by a force is:

W=Fd cos \theta

where

F is the magnitude of the force

d is the displacement

\theta is the angle between the direction of the force and the displacement

In this situation, the tension in the string always points in a radial direction (towards the pivot of the pendulum), while the displacement of the mass is tangential (it follows a circular trajectory): this means that the tension and the displacement are always perpendicular to each other, so in the formula

\theta=90^{\circ}, cos \theta = 0

and so the work done is zero.

You might be interested in
Over a span of 6.0 seconds, a car changes it's speed from 89 km/h to 37 km/h. What is its average acceleration in meters per sec
scoundrel [369]

Acceleration = (change in speed) / (time for the change)

change in speed = (speed at the end) - (speed at the beginning)

change in speed = (37 km/hr) - (89 km/hr) = -52 km/hr

Acceleration = (-52 km/hr) / (6 sec)

Acceleration = (-26/3) km/(hr·sec)

Units: (1/hr·sec) · (hr/3600 sec) = 1 / 3600 sec²

(-26/3) km/(hr·sec) = (-26/3) km/(3600 sec²)

= -26,000/(3 · 3600) m/s²

<em>Acceleration = -2.41 m/s²</em>

3 0
3 years ago
In transistor emitter current is equal to which current?
Paladinen [302]
In transistor,
Emitter current is equal to the sum of base current and collector current.
Thanks!
8 0
2 years ago
What will happen to the charge and potential difference if the plate area were increased while the plate separation remains unch
Alenkinab [10]

Answer:

Potential difference and charge will also increase.

Explanation:

Asking that :

What will happen to the charge and potential difference if the plate area were increased while the plate separation remains unchanged?

The charge is directly proportional to area of the plate. That is, increase in area of the plate of a capacitor will lead to the increase in the charges between the plates.

And since charge is also proportional to the magnitude of potential difference between the plates from the definition of capacitance of a capacitor which says that:

Q = CV

Therefore, increase in the area of the plate will also lead to increase in potential difference between the plates.

Therefore, if the plate area were increased while the plate separation remains unchanged, the charge and potential difference between them will also increase.

5 0
3 years ago
Assuming the diode is ideal but with a forward voltage drop of. 65 volts, what is the current in ma if v1=0v, and r1=490ω?
weeeeeb [17]

The current in the ideal diode with forward biased voltage drop of 65V is 132.6 mA.

To find the answer, we have to know more about the ideal diode.

<h3>What is an ideal diode?</h3>
  • A type of electronic component known as an ideal diode has two terminals, only permits the flow of current in one direction, and has less zero resistance in one direction and infinite resistance in another.
  • A semiconductor diode is the kind of diode that is used the most commonly.
  • It is a PN junction-containing crystalline semiconductor component that is wired to two electrical terminals.
<h3>How to find the current in ideal diode?</h3>
  • Here we have given with the values,

                       V_2=65V\\V_1=0V\\R_1=490Ohm.

  • We have the expression for current in mA of the ideal diode with forward biased voltage drop as,

                I=\frac{V_2-V_1}{R_1} =\frac{65}{490} =132.6mA

Thus, we can conclude that, the current in mA of the ideal diode with forward biased voltage drop of 65 V is 132.6.

Learn more about the ideal diode here:

brainly.com/question/14988926

#SPJ4

7 0
1 year ago
Helpppp plz heeeeeeeeeeeelp
diamong [38]

Answer:that

Explanation:

8 0
2 years ago
Other questions:
  • An atom that changes so that it has an<br> electrical charge is a(n)
    8·1 answer
  • NVM hwaskdhslak djklasj dkjaskj dklasj kJKS KLj klskla
    5·2 answers
  • The asteroid Ceres has a mass 6.797 × 1020 kg and a radius of 472.9 km. What is g on the surface? The value of the universal gra
    13·1 answer
  • What is the answer to this question
    14·1 answer
  • Potential energy of an apple is 6j. the apple is 3.00m high. what is the mass of the apple?​
    13·1 answer
  • Which of these are not a natural resources: solar energy, wood, iron, diamonds.
    10·1 answer
  • How does object float
    8·2 answers
  • If you act without reason or sound judgement, people will describe you as __________.
    9·1 answer
  • The unit of area is derived unit why​
    6·2 answers
  • An apple in a tree has a gravitational potential energy of 175j. And a mass of 0.36 how high from the ground is the apple
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!