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
sleet_krkn [62]
3 years ago
10

A. A child is twirling a 1.52 kg object in a vertical circle with a radius of 67.6

Physics
1 answer:
steposvetlana [31]3 years ago
6 0

Answer:

(a) 4.21 m/s

(b) 24.9 N

Explanation:

(a) Draw a free body diagram of the object when it is at the bottom of the circle.  There are two forces on the object: tension force T pulling up and weight force mg pulling down.

Sum the forces in the radial (+y) direction:

∑F = ma

T − mg = m v² / r

v = √(r (T − mg) / m)

v = √(0.676 m (54.7 N − 1.52 kg × 9.8 m/s²) / 1.52 kg)

v = 4.21 m/s

(b) Draw a free body diagram of the object when it is at the top of the circle.  There are two forces on the object: tension force T pulling down and weight force mg pulling down.

Sum the forces in the radial (-y) direction:

∑F = ma

T + mg = m v² / r

T = m v² / r − mg

T = (1.52 kg) (4.21 m/s)² / (0.676 m) −  (1.52 kg) (9.8 m/s²)

T = 24.9 N

You might be interested in
Outside our solar system the closest star to earth is Proxima century life from the start takes 2200000 minutes to reach earth.
s2008m [1.1K]

Answer:

2200000 = 2.2E6 min for light from Proxima to reach earth

8.3 min from light sun to reach earth

2.2E6/8.3 = 2.56E5   times for light from Proxima

Proxima is about 256,000 times farther away than the sun

Since the sun is about 93,000,000 = 9.3E7 miles from earth

Proxima is then 9.3E7 * 2.56E5 = 2.4E13 miles away

Note - the speed of light is

3.00E8 m/s * 60 s/min / 1000 m/km = 1.8E7 km/min as given

5 0
2 years ago
Astronomers can now report that active star formation was going on at a time when the universe was only 20% as old as it is toda
disa [49]

Answer:

First, as you may know, the light travels at a given velocity.

In vaccum, this velocity is c = 3x10^8 m/s.

And we know that:

distance = velocity*time

Now, if some object (like a star ) is really far away, the light that comes from that star may take years to reach the Earth.

This means that the images that the astronomers see today, actually happened years and years ago (So the night sky is like a picture of the "past" of the universe)

Also, for example, if an astronomer sees some particular thing, he can apply a model (a "simplification" of some phenomena that is used to simplify it an explain it) and with the model, the scientist can infer the information of the given thing some time before it was seen.

8 0
3 years ago
Can some answer 7 a and b please
pav-90 [236]

Answer:

a.After 15 second Mr Comer's speed =  1.7 m/s

b.Distance travelled by Mr.Comer in 15 seconds  =   18.75\ m

Explanation:

a. Lets recall our first equation of motion V_{f} =V_{i} + at

Now we know that V_{i} = 0.8m/s , a = 0.06\ m/s^2 and

t = 15 \ sec

Plugging the values we have.

V_{f} =V_{i} + at

V_{f} =0.8 + 0.06 \times 15

V_{f} =0.8+ 0.9

V_{f} =1.7 m/s

Then Mr.Comer's speed after 15 sec = 1.7ms^-1

b.

Lets find the distance and recall our third equation of motion.

V_{f} ^2-V{i}^2 = 2as

So s = distance covered.

Dividing both sides with 2a we have.

\frac{V_{f} ^2-V{i}^2}{2a} = 2as

Plugging the values.

\frac{(1.7)^2-(0.8)^2}{2\times0.06} = 2as

s= 18.75\ m

So Mr.Comer will travel a distance of s= 18.75\ m.

4 0
3 years ago
State Schrodinger equation.​
Elenna [48]

Hi!Schrodinger equation is written as HΨ = EΨ, where h is said to be a Hamiltonian operator.

3 0
2 years ago
What happens during the process of deposition
frez [133]
Deposition is the process in which sediments, soil and rocks are added to a landform or landmass. When previous weathers surface material , is deposited to a building layer of sediment .
8 0
3 years ago
Other questions:
  • A container of negligible heat capacity has in it 456 g of ice at - 25 . 0°C . Heat is supplied to the container at the rate of
    10·1 answer
  • Describe how Rutherford's experiments changed the accepted scientific model of the atom.
    9·1 answer
  • Please help! I have another part to this too.
    8·1 answer
  • On a distant planet, golf is just as popular as it is on earth. A golfer tees off and drives the ball 2.50 times as far as he wo
    13·1 answer
  • Humans impact the Earth in good AND bad ways. <br><br>A) True <br><br>B) False
    9·1 answer
  • What amount of heat is absorbed by 257 g of water heated from 18° C to 63° C? The specific heat of water is 4.18 J/g°C.
    12·1 answer
  • I need help please will mark brainliest
    7·1 answer
  • What important component is still scarce for American manufacturers, which had 40 days' worth before the pandemic but only had a
    15·1 answer
  • if your oven uses a 220.0 volt line and draws a maximum 8.00 A current what is the resistance of the oven when it is fully heate
    15·1 answer
  • What is the relationship between mass and weight in physics?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!