I need help. Is this right? ITS SO

Every sample of a pure substance has exactly the same composition and the same properties. true or false

kirill115 [55]

False, that does not apply to some

7 0

2 years ago

RACTIC PTUDIES

Amanda [17]

Answer:

The illumination on the book before the lamp is moved is 9 times the illumination after the lamp is moved.

Explanation:

The distance of the book before the lamp is moved, $d_{b} = 30 cm$

The distance of the book after the lamp is moved, $d_{a} = 90 cm$

Illumination can be given by the formula, $E = \frac{P}{4 \pi d^{2} }$

Illumination before the lamp is moved, $E_{b} = \frac{P}{4 \pi d_{b} ^{2} }$

Illumination after the lamp is moved, $E_{a} = \frac{P}{4 \pi d_{a} ^{2} }$

$\frac{E_{a}}{E_{b}} } = \frac{\frac{P}{4 \pi d_{a} ^{2} } }{\frac{P}{4 \pi d_{b} ^{2} } }$

$\frac{E_{a} }{E_{b} } = \frac{d_{b} ^{2} }{d_{a} ^{2}} \\\frac{E_{a} }{E_{b} } = \frac{30^{2} }{90 ^{2}}\\\frac{E_{a} }{E_{b} } =\frac{900 }{8100}\\\frac{E_{a} }{E_{b} } =\frac{1 }{9}$

$E_{b} = 9E_{a}$

The illumination on the book before the lamp is moved is 9 times the illumination after the lamp is moved.

6 0

2 years ago

What is your initial speed if you accelerate at 5.8 m/s/s for 3.0 seconds and achieve a final speed of 45 m/s?

Natali5045456 [20]

Answer:

27.6 m/s

Explanation:

hopefully it makes sense and is visible

:)

8 0

1 year ago

Sending food to a country that has been hit by a hurricane is an example of which foreign policy tool?

sasho [114]

International Disaster Management or FEMA

8 0

2 years ago

Read 2 more answers

What are three benefits of being assertive and what are three tips to help you develop an assertive style of communication? (Sit

uysha [10]

1. The benefits of been assertive include the following:
a. It improve one self image: When you choose to be assertive, you adopt a self realistic image.
b. It enhance how we understand others: Been assertive helps you to see others in a more realistic context.
c. Promote self awareness and self confidence: Been assertive helps you to develop a greater respect for your own points of view when dealing with issues.
d. Been assertive is a less stressful way of communicating.

2. The three steps needed to develop assertive communication, include:
a. Learn to 'no' more often: refuse to please everyone and do not behave according to people expectations of you. Be yourself.
b. Your tone must be properly turned when talking: Do not raise your voice or rush a communication. Be calm and cool when talking.
c. Be open to communication: Be willing to discuss issues until a suitable solution is found.
d. Pay attention to non-verbal communication of others: Keep eye contact when communicating and pay attention to other body gestures.

5 0

2 years ago