Can anyone help me with this assignment? please and thank you

Which of these instruments is listed with the wrong type of lens that it uses?

VikaD [51]

The wrong type of lens-Microscope, concave

Explanation:

A microscope Basically uses two convex lenses to magnify an object, or specimen.

There are 2 lenses in a microscope

Object Lens:The lens that is closer to the object
Eyepiece:The lens that is closer to the eye

Both the object lens and the eyepiece, is a convex lens.

3 0

3 years ago

One method of determining the location of the center of gravity of a person is to weigh the person as he/she lies on a board of

andrey2020 [161]

Answer:

x = 1.018 m

Explanation:

given,

height of man = 190 cm

= 1.9 m

scale reading on left = 450 N

scale reading on the right = 390 N

Let center of gravity of man be x distance from feet, feet is on right side.

For system to be in equilibrium moment about center should be equal to zero.

∑M = 0

now,

450(1.9 - x ) - 390 × x = 0

450(1.9 - x ) = 390 × x

855 - 450 x = 390 x

840 x = 855

$x = \dfrac{855}{840}$

x = 1.018 m

hence, point of center of gravity from feet is equal to x = 1.018 m

7 0

4 years ago

Complete the following sentences.

MrMuchimi

force pull the ball towards it with a force called gravity.
newton

5 0

3 years ago

A 2.64-kg copper part, initially at 400 K, is plunged into a tank containing 4 kg of liquid water, initially at 300 K. The coppe

marin [14]

Answer:

a) $T_f=305.7049\ K$

b) $\Delta S=313.51\ J.K^{-1}$

Explanation:

Given:

mass of copper, $m_c=2.64\ kg$

initial temperature of copper, $T_{ic}=400\ K$

specific heat capacity of copper, $c_c=385\ J.kg^{-1}.K^{-1}$

mass of water, $m_w=4\ kg$

initial temperature of water, $T_{iw}=300\ K$

specific heat capacity of water, $c_w=4200\ J.kg^{-1}.K^{-1}$

a)

∵No heat is lost in the environment and the heat is transferred only between the two bodies:

Heat rejected by the copper = heat absorbed by the water

$2.64\times 385\times (400-T_f)= 4\times 4200\times (T_f-300)$

$T_f=305.7049\ K$

b)

Now the amount of heat transfer:

$Q=m_c.c_c.(T_{ic}-T_{f})$

$Q=2.64\times 385\times (400-305.7049)$

$Q=95841.5841\ J$

∴Entropy change

$\Delta S=\frac{dQ}{T}$

$\Delta S=\frac{95841.5841}{305.7049}$

$\Delta S=313.51\ J.K^{-1}$

5 0

4 years ago

Is gas matter? How do you know? Hint: Remember there are 2 things we need to be considered matter.

astra-53 [7]

Answer:

Gas is a state of matter that has no fixed shape and no fixed volume.

In addition to solids and liquids, gases are also a physical state in which matter can occur. All gases have weight. Unlike solids and liquids, gases will occupy the entire container that encloses them.

matter is "anything that has mass and volume (occupies space)

Gases have mass. The space between gas particles is empty. Gases can be formed as products in chemical reactions. Gas particles can form bonds between them under certain conditions

Gases have volume which isn't fixed (no fixed volume) and no fixed shape. Gases expand to fill the space available. They can also be compressed into a very small space.

Explanation:

7 0

3 years ago