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Triss [41]
3 years ago
12

1. What is meant by half-life?

Physics
1 answer:
Bezzdna [24]3 years ago
8 0
1. The time for a radioactive sample to reduce to half of its original mass.
4. 10% of 232 is 23.2 times 6 equals 139.2
68.9 x6 equals 413.4
5. 0.37kg
6. 2000 years
7. 6.84 seconds
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Asap PLEASE HELP!!!!<br> Match these vocabulary words with their definitions.
lubasha [3.4K]
1. Isotherm
2. Labrador current
3. Longitude
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6. Maritime
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mark me brainliest please!
3 0
2 years ago
A device called oacillatwr is used to swnd waves along a streatched string to send waves along a streatched string. The string i
vitfil [10]

Answer:

Frequency = 2m/s1m=2 waves/s, or 2 Hz

A wave is traveling at a speed of 2 m/s and has a frequency of 2 Hz.

Explanation:

wd Calculating Wave Frequency or Wavelength from Wave Speed

The equation for wave speed:

Frequency = SpeedWavelength or Wavelength = SpeedFrequency

Therefore, if you know the speed of a wave and either the wavelength or wave frequency, you can calculate the missing value.

For example, suppose that a wave is traveling at a speed of 2 meters per second and has a wavelength of 1 meter. Then the frequency of the wave is:

- Frequency = 2m/s1m=2 waves/s, or 2 Hz

A wave is traveling at a speed of 2 m/s and has a frequency of 2 Hz. What is its wavelength?

- Substitute these values into the equation for wavelength:

- Wavelength = 2m/s2waves/s=1 m

See more: https://www.ck12.org/physics/wave-speed/lesson/Wave-Speed-MS-PS/

3 0
3 years ago
A charge of 1.5 × 1015 coulombs moves from point A to a lower potential at point B. The electric field is uniform at 2.5 × 10-5
Jlenok [28]
The work done by the electric field is given by:
W=q \Delta V
where q is the charge, and \Delta V is the potential difference between point A and B. But the potential difference is equal to
\Delta V = E d
where E is the intensity of the electric field, while d is the distance between the two points A and B.
Therefore, the work done by the field is
W=q \Delta V =qEd=
=1.5\cdot10^{15}~C \cdot 2.5\cdot 10^{-5}~N/C \cdot 1.7\cdot 10^{-2}~m = 6.38\cdot 10^8~J
3 0
2 years ago
You are sitting on a merry-go-round of mass 200 kg and radius 2m that is at rest (not spinning). Your mass is 50 kg. Your friend
Arada [10]

Answer:

Explanation:

Incomplete question

This is the complete question

You are sitting on a merry-go-round of mass 200 kg and radius 2m that is at rest (not spinning). Your mass is 50 kg. Your friend pushes the edge of the merry go round with 100 N of force, applied at a 90 deg angle. (hint: the merry-go-round is a disk).

a. How much torque did your friend apply?

b. What is your angular acceleration if you are sitting in the middle of the merry-go-round?

c. What is your angular acceleration if you are sitting at the edge of the merry-go-round?

d. Which angular acceleration is larger and why?

Given that,

Mass of Merry go round

M = 200kg

Radius of Merry go round

R = 2m

Mass of person on sitting on the merry go round

m = 50kg

Force applied to push the merry go round

F = 100N

The force is applied at an angle of 90°

θ = 90°

a. Torque?

The torque can calculated using the formula

τ = R × F. This is the cross product of R and F

τ = R•F•Sinθ

Then,

τ = 2 × 100 × Sin90

τ = 200 Nm

b. Angular acceleration if the person is sitting at the middle

Since the boy is sitting at the middle, then is distance from the centre is r' = 0

We know that

τ = I•α

Where, I is moment of inertial and α is angular acceleration

So, we need to find the moment of inertial

Moment of inertial is calculated using

I = MR², since the merry go round is model as a disk

Then,

Total moment of inertial of the boy and the merry go round

I = MR² + mr'²

I = 200 × 2² + 50 × 0²

I = 800 kgm²

So, τ = I•α

α = τ / I

α = 200/800

α = 0.25 rad/s²

c. Angular acceleration if the person is sitting at the edge

Since the person is sitting at the edge, then is distance from the centre is r = R = 2m

We know that

τ = I•α

Where, I is moment of inertial and α is angular acceleration

So, we need to find the moment of inertial

Moment of inertial is calculated using

I = MR², since the merry go round is model as a disk

Then,

Total moment of inertial of the boy and the merry go round

I = MR² + mR²

I = 200 × 2² + 50 × 2²

I = 800 + 200

I = 1000kgm²

So, τ = I•α

α = τ / I

α = 200/1000

α = 0.2 rad/s²

d. The angular acceleration when the person is sitting at the center is greater than when the person is sitting at the edge.

This is due to that the boy does not have any moment of inertial at the center. Also, at the edge the boy has a moment inertial. So, the moment of inertia at the edge is greater than the moment of inertial at the center

Then, we know that, α = τ / I

So, angular acceleration is inversely proportional to the moment of inertial, this implies that at the moment of inertial increases the angular acceleration reduces and as the moment of inertia decrease the angular acceleration decreases.

6 0
3 years ago
At take off, a plane flies 100 km north before turning to fly 200 km east. How far is its destination from where the plane took
koban [17]

224 km I did the quiz today

7 0
2 years ago
Read 2 more answers
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