2 years ago

What is true about an object in free fall?

1 answer:

5 0

The only force being acted upon it is gravity. A ball that was thrown downward off a building isn't in freefall, because it had initial velocity. A piece of paper can't necessarily be in free fall because it is affected by air resistance.

You might be interested in

What are some errors made while doing measuring with a triple beam balance lab

nydimaria [60]

Make sure the triple beam balance is at 0 before you begin.

7 0

3 years ago

Read 2 more answers

In a clear cup there are three substances. Their densities are 3, 1, and 2. From top of the cup to the bottom, what would the or

Vesnalui [34]

Answer:

1, 2 and 3

Explanation:

The most dense substance will settle at the bottom of the cup

4 0

2 years ago

Practical steam engines utilize 450ºC steam, which is later exhausted at 270ºC.

Naily [24]

(a) 0.249 (24.9 %)

The maximum efficiency of a heat engine is given by

$\eta = 1-\frac{T_C}{T_H}$

where

Tc is the low-temperature reservoir

Th is the high-temperature reservoir

For the engine in this problem,

$T_C = 270^{\circ}C+273=543 K$

$T_H = 450^{\circ}C+273=723 K$

Therefore the maximum efficiency is

$\eta = 1-\frac{T_C}{T_H}=1-\frac{543}{723}=0.249$

(b-c) 0.221 (22.1 %)

The second steam engine operates using the exhaust of the first. So we have:

$T_H = 270^{\circ}C+273=543 K$ is the high-temperature reservoir

$T_C = 150^{\circ}C+273=423 K$ is the low-temperature reservoir

If we apply again the formula of the efficiency

$\eta = 1-\frac{T_C}{T_H}$

The maximum efficiency of the second engine is

$\eta = 1-\frac{T_C}{T_H}=1-\frac{423}{543}=0.221$

8 0

3 years ago

The purpose of the little Albert experiment?

HACTEHA [7]

Answer:

The aim of Watson and Rayner was to condition a phobia in an emotionally stable child.

Explanation:

Does this help?

3 0

3 years ago

C-14 is an isotope of the element carbon. How does it differ from the carbon atom seen here? A) C-14 has two more protons. B) C-

mylen [45]

Answer:

C-14 has two more neutrons.

Explanation:

4 0

3 years ago

Read 2 more answers