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3 years ago

Which statement is true?

2 answers:

8 0

The first statement is true because speed, being a scalar quantity, is the rate at which an object covers distance. The average speed is the distance (a scalar quantity) per time ratio. Speed has nothing to do with direction. On the other hand, velocity is a vector quantity because direction is needed for this.

Romashka-Z-Leto [24]3 years ago

8 0

Answer : The correct option is, Speed is a scalar quantity and velocity is a vector quantity.

Explanation :

Speed : It is defined as the distance traveled by the object per unit time.

It is a scalar quantity because it does not depends on the direction of an object but it depends on the magnitude of the object. The unit of speed is, meter/second or m/s.

For example : The speed is written as, 44 m/s.

Velocity : It is defined a the displacement of an object with respect to the time.

It is a vector quantity because it depends on both direction and as well as on magnitude of the object. The unit of velocity is, meter/second or m/s.

For example : The velocity is written as, 44 m/s north.

Hence, the correct option is, Speed is a scalar quantity and velocity is a vector quantity.

You might be interested in

In a sample of oxygen gas at room temperature, the average kinetic energy of all the balls stays constant. Which postulate of ki

Levart [38]

Answer:

Collisions between gas particles are elastic; there is no net gain or loss of kinetic energy.

Explanation:

When a gas is paced in a container, the molecules of the gas have little or no intermolecular interaction between them. There is a lot of space between the molecules of the gas.

The gas molecules move at very high speed and collide with each other and with the walls of container.

The collision of these particles with each other is perfectly elastic hence the kinetic energy of the colliding gas particles do not change.

7 0

3 years ago

How much heat is required to raise the temperature of 65.8 grams of water from 31.5ºC to 46.9ºC?

vodomira [7]

Answer: 1,013.32 cal × 4.18 J/cal = 4,235.68 J

Explanation:

1) Data:

Water ⇒ C = 1 cal/g°C

m = 65.8 g

Ti = 31.5°C

Tf = 36.9°C

Heat, Q = ?

2) Formula:

Q = mCΔT

3) Calculations:

Q = 65.8g × 1 cal/g°C × (46.9°C - 31.5°C) = 1,013.2 cal

4) You can convert from calories to Joules using the conversion factor:

1 cal = 4.18 J

⇒ 1,013.32 cal × 4.18 J/cal = 4,235.68 J

3 0

3 years ago

How does the sun heat the side of the Earth facing away from it?

Evgen [1.6K]

Answer:

The sun radiates energy in all directions.

Explanation:

Most of it dissipates into space, but the tiny fraction of the sun's energy that reaches Earth is enough to heat the planet and drive the global weather system by warming the atmosphere and oceans

3 0

3 years ago

What is the theoretical yield of Calcium if we begin with 12.6 grams of Aluminium?

AlladinOne [14]

The question is incomplete, here is the complete question:

The given chemical reaction is:

$2Al+3Cu(NO_3)_2\rightarrow 3Cu+2Al(NO_3)_3$

What is the theoretical yield of Calcium if we begin with 12.6 grams of Aluminium?

Answer: The theoretical yield of copper is 44.48 grams

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

Given mass of aluminium = 12.6 g

Molar mass of aluminium = 27 g/mol

Putting values in equation 1, we get:

$\text{Moles of aluminium}=\frac{12.6g}{27g/mol}=0.467mol$

The given chemical equation follows:

$2Al+3Cu(NO_3)_2\rightarrow 3Cu+2Al(NO_3)_3$

By Stoichiometry of the reaction:

2 moles of aluminium produces 3 moles of copper

So, 0.467 moles of aluminium will produce = $\frac{3}{2}\times 0.467=0.7005mol$ of copper

Now, calculating the mass of copper from equation 1, we get:

Molar mass of copper = 63.5 g/mol

Moles of copper = 0.7005 moles

Putting values in equation 1, we get:

$0.7005mol=\frac{\text{Mass of copper}}{63.5g/mol}\\\\\text{Mass of copper}=(0.7005mol\times 63.5g/mol)=44.48g$

Hence, the theoretical yield of copper is 44.48 grams

4 0

3 years ago

Which skeleton equation represents a neutralization reaction? Mg + O2 MgO AlCl3 Al + Cl2 Li + HNO3 H2 + LiNO3 HBr + LiOH LiBr +

creativ13 [48]

Neutralization reaction is the reaction between acid and base.
There the neutralization reaction is:

HBr + LiOH ----------> LiBr + H2O.

Hope this helps!

5 0

2 years ago

Read 2 more answers