All categories

3 years ago

Select all of the answers that apply.

2 answers:

5 0

Researchers found the "cosmic microwave background radiation", which is a heat imprint left over from the big bang.

The redshift of light emitted by most galaxies indicates the universe is expanding.

Over [174]3 years ago

5 0

Researchers found the "cosmic microwave background radiation", which is a heat imprint left over from the big bang.

The redshift of light emitted by most galaxies indicates the universe is expandinding.

You might be interested in

Recall that if the colliding objects have hard surfaces, the collision is elastic. Based on this description, which bumper desig

Andrews [41]

Answer:

wheres the pic

Explanation:

3 0

3 years ago

Two trains are traveling on the same track and in the same direction. The first train, which is behind the second train, blows a

Andrews [41]

Answer:

37.545 m/s

Explanation:

f' = Actual frequency of horn = 269 Hz

f = Observed frequency of horn = 290 Hz

v = Speed of sound in air = 343 m/s

$v_0$ = Speed of second train = 13.7 m/s

$v_s$ = Speed of first train

From Doppler effect we have

$f=f'\dfrac{v-v_0}{v-v_s}\\\Rightarrow v_s=v-\dfrac{f'}{f}(v-v_0)\\\Rightarrow v_s=343-\dfrac{269}{290}(343-13.7)\\\Rightarrow v_s=37.545\ m/s$

The speed of the first train is 37.545 m/s

5 0

3 years ago

What happened to the maximum height of consecutive swings

GarryVolchara [31]

Answer:

we need more info

Explanation:

3 0

3 years ago

A roller coaster has a "hump" and a "loop" for riders to enjoy (see picture). The top of the hump has a radius of curvature of 1

aivan3 [116]

Answer:

Part a)

$F_n = 306 N$

Part b)

$v = 12.1 m/s$

So this speed is independent of the mass of the rider

Explanation:

Part a)

By force equation on the rider at the position of the hump we can say

$mg - F_n = ma_c$

now we will have

$mg - F_n = \frac{mv^2}{R}$

$F_n = mg - \frac{mv^2}{R}$

now we have

$F_n = 100(9.81) - \frac{100(9^2)}{12}$

$F_n = 981 - 675$

$F_n = 306 N$

Part b)

At the top of the loop if the minimum speed is required so that it remains in contact so we will have

$F_n + mg = ma_c$

$F_n = 0$ at minimum speed

$mg = \frac{mv^2}{R}$

$v = \sqrt{Rg}$

$v = \sqrt{15 \times 9.81}$

$v = 12.1 m/s$

So this speed is independent of the mass of the rider

5 0

3 years ago

Your body is receiving backround radiation all the tim. Explain

adoni [48]

The uniform microwave radiation remaining from the Big Bang.

So, your body is always having background radiation and that means space!

3 0

3 years ago