The atmosphere protects us from all of the following except Meteorites The sun's rays Pollution Wind

Diffraction is observable when the opening is ______ than the wavelength.

masya89 [10]

Diffraction is observable when the is smaller than the wavelength

5 0

4 years ago

Light travels at a constant speed of about 300,000 km/s. This speed is referred to as the speed of light. A light year is the di

Rama09 [41]

Based on the information in the question, a light year is the distance traveled light in one year. Then if the light from the star Centauri takes 4.2 years to reach the earth, then its distance from earth is 4.2 light years.

7 0

3 years ago

Read 2 more answers

Darren drives to school in rush hour traffic and averages 28 mph. He returns home in mid-afternoon when there is less traffic an

Gala2k [10]

Answer:

distance between school and home is 21 miles

Explanation:

given data

in rush hour speed s1 = 28 mph

less traffic speed s2 = 42 mph

time t = 1 hr 15 min = 1.25 hr

to find out

distance d

solution

we consider here distance home to school is d and t1 time to reach at school

we get here distance equation when we go home to school that is

distance = 28 × t1 .......................1

and when we go school to home distance will be

distance = 42 × ( t - t1 )

distance = 42 × ( 1.25 - t1 ) ...................2

so from equation 1 and 2

28 × t1 = 42 × ( 1.25 - t1 )

t1 = 0.75

so

from equation 1

distance = 28 × t1

distance = 28 × 0.75

distance = 21 miles

4 0

3 years ago

A driver averaged 64 mph and took 3½ hours to travel from st. Louis to chicago. Based on this, what is the distance between st.

sammy [17]

Average speed of the driver is given as

$v = 64 mph$

if he moved for total time t = 3.5 hours

so the distance between the tow is given as

$d = v* t$

$d = 64 * 3.5$

$d = 224 miles$

so the distance between St. Louis and Chicago is 224 miles

6 0

3 years ago

A battery with an emf of 24.0 V is connected to a resistive load. If the terminal voltage of the battery is 16.1 V and the curre

lions [1.4K]

Answer:

2.03 Ω

Explanation:

EMF: This can be defined as the potential difference of a cell when it is not delivering any current. The S.I unit of Emf is Volt.

The formula of emf is given as,

E = I(R+r)............................ Equation 1

Where E = Emf, I = current, R = External resistance, r = internal resistance.

Make r the subject of the equation

r = (E-IR)/I........................ Equation 2

Note: From ohm's law, V = IR.

r = (E-V)/I........................ Equation 3

Where V = Terminal voltage

Given: E = 24 V, I = 3.9 A, V = 16.1 V.

Substitute into equation 3

r = (24-16.1)/3.9

r = 7.9/3.9

r = 2.03 Ω

6 0

3 years ago