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3 years ago

PLSSSSS HELP!!!!!!! ASAP!!!!! MARK BRAINLIEST!!!!

Physics

1 answer:

Ymorist [56]3 years ago

5 0

Answer: I would say the answer is B.

Explanation: It looks and sounds the most correct.

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As the temperature of a blackbody increases, what happens to the peak wavelength of the light it radiates

lidiya [134]

Answer:

The peak wavelength of the light it irradiates decreases

Explanation:

As the temperature of a blackbody increase, the peak wavelength of the light it radiates decreases, this follows Wien's Law.

A blackbody is an ideal substance that emits all frequencies of light and also has the ability to absorb them as well.

Wiens displacement law, explains that the position of the peak wavelength of the thermal radiation emitted by bodies can change with temperature, and as the temperature increases beyond a certain point, the wavelength begins to reduce. This often changes the colour of the light emitted from heated objects.

3 0

3 years ago

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A small 20-kilogram canoe is floating downriver at a speed of 2 m/s. What is the canoe's kinetic energy?

MariettaO [177]

Ek=1/2mv^2 = (20)(1/2)(2x2) =40

8 0

3 years ago

Read 2 more answers

A stone is dropped from the upper observation deck of a tower, 250 m above the ground. (Assume g = 9.8 m/s2.) (a) Find the dista

Vitek1552 [10]

(a) $y(t)=250 - 4.9 t^2$

For an object in free-fall, the vertical position at time t is given by:

$y(t) = h + ut - \frac{1}{2}gt^2$

where

h is the initial vertical position

u is the initial vertical velocity

g = 9.8 m/s^2 is the acceleration of gravity

t is the time

In this problem,

h = 250 m

u = 0 (the stone starts from rest)

So, the vertical position of the stone is given by

$y(t) = 250 - \frac{1}{2}(9.8) t^2 = 250 - 4.9 t^2$

(b) 7.14 s

The time it takes for the stone to reach the ground is the time t at which the vertical position of the stone becomes zero:

y(t) = 0

Which means

$y(t) = h - \frac{1}{2}gt^2=0$

So for the stone in the problem, we have

$250 - 4.9 t^2 = 0$

Solving for t, we find:

$t=\sqrt{\frac{250}{4.9}}=7.14 s$

(c) -70.0 m/s (downward)

The velocity of an object in free fall is given by the equation

$v(t) = u - gt$

where

u is the initial velocity

g = 9.8 m/s^2 is the acceleration of gravity

t is the time

Here we have

u = 0

So if we substitute t = 7.14 s, we find the velocity of the stone at the time it reaches the ground:

$v=0-(9.8 m/s^2)(7.14 s)=-70.0 m/s$

The negative sign means the direction of the velocity is downward.

(d) 6.94 s

In this situation, the stone is thrown downward with an initial speed of 2 m/s, so its initial velocity is

u = -2 m/s

So the equation of the vertical position of the stone in this case is

$y(t) = h + ut - \frac{1}{2}gt^2=250 - 2t - 4.9 t^2$

By solving the equation, we find the time t at which the stone reaches the ground.

We find two solutions:

t = -7.35 s

t = 6.94 s

The first solution is negative, so it has no physical meaning, therefore we discard it. So, the time it takes for the stone to reach the ground is:

t = 6.94 s

6 0

3 years ago

Far from any other masses, two masses, m1 and m2, are interacting gravitationally. The value for the mass of m1 suddenly doubles

NNADVOKAT [17]

<span>It also doubles The gravitational force between two masses is expressed as: F = G*m1*m2/r^2 where F = Force between the two masses m1 = Mass of object 1 m2 = Mass of object 2 r = distance between centers of object 1 and object 2 G = Gravitational constant The exact values of G, m1, m2, and r don't matter since all except for m1 is held constant. And when m1 suddenly doubles, the force attracting the two object to each other also doubles.</span>

5 0

4 years ago

If an automobile slows from 26 m/s to 18 m/s in a period of 4.0 s, what was the average acceleration?

geniusboy [140]

Answer: -2m/s²

Explanation:

Each second, the acceleration decreases of 2m/s²

N.B.: in physics, deceleration is also acceleration.

6 0

3 years ago