A dog travels 18 meters south across the backyard in 11 seconds. What is the dog's speed?

In the mixtures lab, you waited to see if the liquid would form lumpy or fluffy masses, which would indicate it was a _____.

Over [174]

B) colloid because i took the test and that the answer

5 0

3 years ago

Read 2 more answers

Which of the following does not use electromagnetic radiation? (Check all that apply)

Nesterboy [21]

I know that refrigerator units do not use electromagnetic radiation
I am not certain about plasma however I believe it doeant either

3 0

3 years ago

An aluminum calorimeter with a mass of 100 g contains 250 g of water. The calorimeter and water are in thermal equilibrium at 10

Alexeev081 [22]

Answer:

a) $c=1822.3214\ J.kg^{-1}.K^{-1}$

b) This value of specific heat is close to the specific heat of ice at -40° C and the specific heat of peat (a variety of coal).

c) The material is peat, possibly.

d) The material cannot be ice because ice doesn't exists at a temperature of 100°C.

Explanation:

Given:

mass of aluminium, $m_a=0.1\ kg$

mass of water, $m_w=0.25\ kg$

initial temperature of the system, $T_i=10^{\circ}C$

mass of copper block, $m_c=0.1\ kg$

temperature of copper block, $T_c=50^{\circ}C$

mass of the other block, $m=0.07\ kg$

temperature of the other block, $T=100^{\circ}C$

final equilibrium temperature, $T_f=20^{\circ}C$

We have,

specific heat of aluminium, $c_a=910\ J.kg^{-1}.K^{-1}$

specific heat of copper, $c_c=390\ J.kg^{-1}.K^{-1}$

specific heat of water, $c_w=4186\ J.kg^{-1}.K^{-1}$

Using the heat energy conservation equation.

The heat absorbed by the system of the calorie-meter to reach the final temperature.

$Q_{in}=m_a.c_a.(T_f-T_i)+m_w.c_w.(T_f-T_i)$

$Q_{in}=0.1\times 910\times (20-10)+0.25\times 4186\times (20-10)$

$Q_{in}=11375\ J$

The heat released by the blocks when dipped into water:

$Q_{out}=m_c.c_c.(T_c-T_f)+m.c.(T-T_f)$

where

$c=$ specific heat of the unknown material

For the conservation of energy : $Q_{in}=Q_{out}$

so,

$11375=0.1\times 390\times (50-20)+0.07\times c\times (100-20)$

$c=1822.3214\ J.kg^{-1}.K^{-1}$

b)

This value of specific heat is close to the specific heat of ice at -40° C and the specific heat of peat (a variety of coal).

c)

The material is peat, possibly.

d)

The material cannot be ice because ice doesn't exists at a temperature of 100°C.

7 0

3 years ago

3. Forces do ________ always cause an object to move.<br> need this ASAP

Finger [1]

Answer:

not

Explanation:

5 0

3 years ago

Read 2 more answers

Which event demonstrates electromagnetic waves transferring energy?

Citrus2011 [14]

Answer:

Sun heating a car sitting in a parking lot

Explanation:

The sun heating a car sitting in a parking lot is an example of electromagnetic waves transferring energy.

Electromagnetic waves are produced from the vibration between electric and magnetic fields.
These waves can be propagated through vacuum with no particles inside of them.
The sun produces electromagnetic radiation through the process of nuclear fusion.
These radiations are used to warm the earth surface.
The sun heating a car sitting a parking lot is one vivid example.

4 0

3 years ago

Read 2 more answers