All categories

3 years ago

Which term refers to a quantity that has both magnitude and direction?

Physics

2 answers:

mezya [45]3 years ago

6 0

Answer:

A vector quantity is a quantity this has both magnitude and direction, so, the answer is C.

just olya [345]3 years ago

5 0

Answer:C

Explanation:

There correct answer Is C, because vector quantities are quantities that has both magnitude and direction

You might be interested in

Starting from zero, the electric current takes 2 seconds to reach half its maximum possible value in an RL circuit with a resist

Leno4ka [110]

Answer:

time=4s

Explanation:

we know that in a RL circuit with a resistance R, an inductance L and a battery of emf E, the current (i) will vary in following fashion

$i(t)=\frac{E}{R}(1-e^\frac{-t}{\frac{L}{R}})$ , where $i$ max= $\frac{E}{R}$

Given that, at i(2)= $\frac{imax}{2} =\frac{E}{2R}$

⇒ $\frac{E}{2R}=\frac{E}{R}(1-e^\frac{-2}{\frac{L}{R}})$

⇒ $\frac{1}{2}=1-e^\frac{-2}{\frac{L}{R}}$

⇒ $\frac{1}{2}=e^\frac{-2}{\frac{L}{R}}$

Applying logarithm on both sides,

⇒ $log(\frac{1}{2})=\frac{-2}{\frac{L}{R}}$

⇒ $log(2)=\frac{2}{\frac{L}{R}}$

⇒ $\frac{L}{R}=\frac{2}{log2}$

Now substitute $i(t)=\frac{3}{4}imax=\frac{3E}{4R}$

⇒ $\frac{3E}{4R}=\frac{E}{R}(1-e^\frac{-t}{\frac{L}{R}})$

⇒ $\frac{3}{4}=1-e^\frac{-t}{\frac{L}{R}}$

⇒ $\frac{1}{4}=e^\frac{-t}{\frac{L}{R}}$

Applying logarithm on both sides,

⇒ $log(\frac{1}{4})=\frac{-t}{\frac{L}{R}}$

⇒ $log(4)=\frac{t}{\frac{L}{R}}$

⇒ $t=log4\frac{L}{R}$

now subs. $\frac{L}{R}=\frac{2}{log2}$

⇒ $t=log4\frac{2}{log2}$

also $log4=log2^{2}=2log2$

⇒ $t=2log2\frac{2}{log2}$

⇒ $t=4$

5 0

3 years ago

Suppose the farthest distance a person can see without visual aid is 53 cm.

natita [175]

Answer: a. 53cm b. Diverging c. 0.02dioptres

Explanation:

Since the person in question cannot see far object clearly, it shows that the individual is suffering from myopia (short sightedness).

If the object distance (u) is 53cm. for the person to be able to see far way, it means the image must be at infinity. This shows image distance v is infinity. Using the lens formula

1/f = 1/u+1/v

1/f = 1/53 + 1/Infinity

1/f = 1/53 + 0

f=53cm

b) The lens used is concave lens (diverging lens) to diverge all rays outwards

c) Power of a lens P will be 1/53.

P = 0.02dioptres

8 0

3 years ago

A mountaintop is a height y above the level ground. A woman measures the angle of elevation of the

Kamila [148]

Refer to the diagram shown below.
We want to find y in terms of d, φ and θ.

By definition,
$tan (\theta) = \frac{y}{x} \\\\ tan( \phi) = \frac{y}{x-d}$

Therefore
y = x tan(θ) (1)
y = (x - d) tan(φ) (2)

Equate (1) and (2).
$(x - d) \, tan(\phi) = x \, tan(\theta) \\ x[tan(\phi) - tan(\theta)] = d \, tan(\phi) \\ x= \frac{d tan(\phi)}{tan(\phi)-tan(\theta)}$

From (1), obtain the required expression for y.

Answer:
$y= \frac{d \, tan(\phi) \, tan(\theta)}{tan(\phi)-tan(\theta)}$

7 0

3 years ago

Choose the correct statement regarding projectile motion in the absence of air resistance. Assume the object is at sea level mov

pishuonlain [190]

Answer:

Explanation:

The magnitude of the acceleration in the x direction is always zero: TRUE.

At the apex, in the y direction the velocity is zero and the accelration is positive. TRUE.

At the apex, in the x direction, the velocity is zero and the acceleration is zero. FALSE. The accelration is zero, but the velocity is the same it had when it was shot.

The magnitude of the velocity in the y direction is always constant. FALSE, it's subject to gravity and it's velocity varies as $v=v_0 - 9.81ms^{-2} t$

At the apex, in the Y direction, the velocity is negative and the acceleration is zero. FALSE. Velocity is zero, Acceleration is $9.81 ms^{-2}$ , towards the negative y axis

7 0

3 years ago

Water has a high specific heat capacity. This means that a lot of energy is needed to change its temperature. True or false?

Leona [35]

Answer:

a true

Explanation:

Water has the high specific heat capacity.

That means it resists to change its temperature when a considerable amount of heat lost or gained

4200J is needed to raise the temperature of 1kg substance by 1 degree Celsius

3 0

3 years ago