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Arturiano [62]
3 years ago
12

Physical changes (2 points)

Physics
1 answer:
xxTIMURxx [149]3 years ago
5 0
Physical changes do not change the identity of the substance. Heat causes chemical reactions. You cannot see chemical changes with the naked eye. The identity of a substance changes like when you burn paper, from paper it turns into ash and produces smoke, which are products from the chemical reactions. 
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1) A sound wave with a frequency of 300 hertz is traveling through a medium at a speed of 320 meters/second. What is its wavelen
timurjin [86]
1. The wavelength is the ratio of the wave's speed to its frequency in hertz or 1/s. This is shown below,
                           λ = s / f = (320 m/s)  / (300 1/s) = 1.07 m
The wavelength is approximately 1.07 m.

2. The frequency is the ratio between speed and the wavelength,
                        f = (330 m/s) / 0.45 m = 733.33 hertz

 
5 0
3 years ago
Read 2 more answers
Paco was driving his scooter west with an initial velocity of 4 m/s. He accelerates at 0.5 m/s2 for 30 seconds.
KonstantinChe [14]

Answer:

V = 19m/s

Explanation:

Given the following data;

Initial velocity, U = 4m/s

Acceleration, a = 0.5m/s²

Time, t = 30 seconds

To find the final velocity, we would use the first equation of motion;

V = U + at

Where;

V is the final velocity.

U is the initial velocity.

a is the acceleration.

t is the time measured in seconds.

V = 4 + 0.5*30

V = 4 + 15

V = 19m/s

Therefore, his final velocity is 19 meters per seconds.

6 0
3 years ago
Read 2 more answers
A car is traveling at 114 m/s and changes its velocity to 77 m/s in 9 sec.
suter [353]

Answer:

<u>Given</u><u> </u><u>-</u>

  • Initial Velocity, u = 114 m/s
  • Final velocity, v = 77 m/s.
  • Time taken, t = 9 sec.

<u>To</u><u> </u><u>find</u><u> </u><u>-</u><u> </u>

  • Acceleration of the car.

<u>Solu</u><u>tion</u><u> </u><u>-</u>

Here, using the equation of motion v = u + at we can find the acceleration easily.

★ Here,

  1. V = Final velocity
  2. U = Initial Velocity
  3. A = Acceleration
  4. T = Time.

<u>Subs</u><u>tituting</u><u> </u><u>the</u><u> </u><u>values</u><u> </u><u>-</u>

→ 77 = 114 + a(9)

→ 9a = 114 - 77

→ 9a = 37

→ a = 37/9

→ a = 4.1 m/s

<u>There</u><u>fore</u><u>,</u><u> </u><u>the</u><u> </u><u>accele</u><u>ration</u><u> </u><u>of</u><u> </u><u>the</u><u> </u><u>car</u><u> </u><u>will</u><u> </u><u>be</u><u> </u><u>4</u><u>.</u><u>1</u><u> </u><u>m</u><u>/</u><u>s</u><u>.</u>

5 0
3 years ago
Write Newton's 3rd law. How would this law relate to a rocket ship taking off from the earth? Would this law affect the rocket s
irina1246 [14]

Answer:

Part A

Newton's 3rd law states that action and reaction are equal and opposite, mathematically, we have;

F_A = -F_B

Where;

F_A = The action force

F_B = The reaction force

Part B

The law indicates that the force with which a rocket ship uses in taking off from the Earth, F_A is equal in magnitude, and opposite in direction to the reaction force of the Earth to the motion of the rocket, (-)F_B

Part C

The law is a universal law, and it will also affect the rocket ship in space, as the force of the jet from the exhaust is directed towards Earth while in space, the rocket is propelled deeper into space

Explanation:

6 0
3 years ago
A body accelerate uniformly from rest at the rate of 3meters per seconds for 8 sec . calculate the distance covered by the body
pishuonlain [190]

Answer:

96 m

Explanation:

Given:

v₀ = 0 m/s

a = 3 m/s²

t = 8 s

Find: Δx

Δx = v₀ t + ½ at²

Δx = (0 m/s) (8 s) + ½ (3 m/s²) (8 s)²

Δx = 96 m

3 0
3 years ago
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