All categories

3 years ago

If the mass of a material is 99 grams and the volume of the material is 22 cm3, what would the density of the material be?

1 answer:

7 0

You are asked to give the answer in <span>g/cm3. So without knowing any single formulae you can just divide grams by cm3.

</span> $\frac{99 grams}{22 cm^{3} }$

= 4.5 g/cm3

You might be interested in

4. What is the acceleration of a plane that changes velocity from 75 m/s to

kompoz [17]

Answer:

$a = \frac{v - u}{t} \\ s = \frac{ {v}^{2} - {u}^{2} }{2a}$

Explanation:

Apply SUVAT

4 0

3 years ago

Alex is asked to move two boxes of books in contact with each other and resting on a rough floor. He decides to move them at the

Over [174]

Answer:

Part a)

$a= 0.32 m/s^2$

Part b)

$F_c = 3.6 N$

Part c)

$F_c = 5.5 N$

Explanation:

Part a)

As we know that the friction force on two boxes is given as

$F_f = \mu m_a g + \mu m_b g$

$F_f = 0.02(10.6 + 7)9.81$

$F_f = 3.45 N$

Now we know by Newton's II law

$F_{net} = ma$

so we have

$F_p - F_f = (m_a + m_b) a$

$9.1 - 3.45 = (10.6 + 7) a$

$a = \frac{5.65}{17.6}$

$a= 0.32 m/s^2$

Part b)

For block B we know that net force on it will push it forward with same acceleration so we have

$F_c - F_f = m_b a$

$F_c = \mu m_b g + m_b a$

$F_c = 0.02(7)(9.8) + 7(0.32)$

$F_c = 3.6 N$

Part c)

If Alex push from other side then also the acceleration will be same

So for box B we can say that Net force is given as

$F_p - F_f - F_c = m_b a$

$9.1 - 0.02(7)(9.8) - F_c = 7(0.32)$

$F_c = 9.1 - 0.02 (7)(9.8) - 7(0.32)$

$F_c = 5.5 N$

3 0

3 years ago

Many web sites describe how to add wires to your clothing to keep you warm while riding your motorcycle. The wires are added to

Tomtit [17]

Answer:

$P=42.075W$

Explanation:

The power provided by a resistor (wire in this case) is given by:

$P=\frac{V^2}{R}$ .

The resistance of a wire is given by:

$R=\frac{\rho L}{A}$

Where for the resistivity the one of the copper should be used: $\rho=1.68\times10^{-8}\Omega m$ .

The area A is that of a circle, which written in terms of its diameter is:

$A=\pi r^2=\pi (d/2)^2=\frac{\pi d^2}{4}$

Putting all together:

$P=\frac{AV^2}{\rho L}=\frac{\pi d^2V^2}{4\rho L}$

Which for our values is:

$P=\frac{\pi (0.00025m)^2(12V)^2}{4(1.68\times10^{-8}\Omega m)(10m)}=42.075W$

7 0

3 years ago

How do i do a Wavelength and frequency problem

KengaRu [80]

Answer:

wavelength = v/f or wavelength equals to velocity over frequency

frequency= v/w or velocity over wavelength

frequency= 1/p or one over period or time

7 0

3 years ago

Help me please, please !

steposvetlana [31]

Answer:

b and d

a, c, e, and f

Explanation:

Ideal gas law:

PV = nRT

Solving for temperature:

T = PV / (nR)

Therefore, temperature is directly proportional to pressure and volume, and inversely proportional to the number of molecules.

T = k PV / N

Let's say that T₀ is the temperature when P = 100 kPa, V = 4 L, and N = 6×10²³.

a) T = k PV / N = T₀

b) T = k (2P) V / N = 2T₀

c) T = k (P/2) (2V) / N = T₀

d) T = k PV / (N/2) = 2T₀

e) T = k P (V/2) / (N/2) = T₀

f) T = k (P/2) V / (N/2) = T₀

b and d have the highest temperature,

a, c, e, and f have the lowest temperature.

8 0

3 years ago

Read 2 more answers