All categories

3 years ago

Please need help with this

Physics

1 answer:

Mademuasel [1]3 years ago

8 0

A 'velocity' is built out of a speed and a direction.

The only item on that list that has a speed and a direction is the <em>first one</em>. The speed is 30 m/s and the direction is south.

You might be interested in

Some element can be either solid or liquid. At the melting point, the liquid has 8 × 10-22 J more enthalpy per atom than the sol

OlgaM077 [116]

Answer:

481.76 J/mol

133.33 K

Explanation:

$N_A$ = Avogadro's number = $6.022\times 10^{23}$

Change in enthalpy is given by

$\Delta H=8\times 10^{-22}\times 6.022\times 10^{23}\\\Rightarrow \Delta H=481.76\ J/mol$

Entropy is given by

$\Delta S=6\times 10^{-24}\times 6.022\times 10^{23}\\\Rightarrow \Delta S=3.6132\ J/mol K$

Latent heat of fusion is given by

$L_f=\Delta H\\\Rightarrow L_f=481.76\ J/mol$

The latent heat of fusion is 481.76 J/mol

Melting point is given by

$T_m=\dfrac{L_f}{\Delta S}\\\Rightarrow T_m=\dfrac{8\times 10^{-22}\times 6.022\times 10^{23}}{6\times 10^{-24}\times 6.022\times 10^{23}}\\\Rightarrow T_f=133.33\ K$

Melting occurs at 133.33 K

3 0

3 years ago

Two speakers hang from racks placed in an open field. When sound of the same frequency comes from both speakers, no sound is hea

Vanyuwa [196]

Answer:

Explanation:

Wgen the sound is emitting from two speakers, the sound waves interfere each other. the locations at which the destructive interference occurs, we get no sound and the locations where constructive interference occurs, the sound occurs at that locations.

8 0

3 years ago

If a tank contains water 4 m deep, what is the pressure at the bottom of the tank? (Neglect the atmospheric pressure.)

makkiz [27]

Given:

Water 4 m deep

Required:

Pressure at the bottom of the tank

Solution:

p2 – p1 = gh

p2 – p1 = p = gh

p = gh = 1000kg/m3 (9.8m/s2)(4m)

6 0

3 years ago

(b) Cable of a microwave oven has three wires inside it which have insulation of different colours black, green and red. Mention

MakcuM [25]

The green is ground. Ideally, no current travels in this one. The red and black are the power and neutral wires but which colors they are depends on a convention. In the US, you will actually have a black (power) and a white (neutral) Here it's red and black and usually in a red/black system the red is the power. Either way there is a potential of 120V rms between them.

8 0

3 years ago

A force of 20 N acts over an area of 2 m2. What is the pressure?

ycow [4]

$\text{Given that,}\\\\\text{Force, F = 20 N.} ~ \\\\ \text{Area , A = 2 m}^2 . \\\\ \text{Pressure, P =? }\\\\P = \dfrac FA = \dfrac{20}2 = 10~~ \text{Nm}^{-2}$

5 0

2 years ago

Read 2 more answers