As a light wave strikes a shiny surface like a piece of polished metal, it will be

You are climbing in the high sierra when you suddenly find yourself at the edge of a fog-shrouded cliff. to find the height of t

sergey [27]

The total time it takes the sound to reach our on top of the cliff (10.0 s) is actually sum of two times:
- the time it takes the rock to hit the ground starting from the top of the cliff, t1
- the time it takes the sound to reach the top of the cliff starting from the ground, t2
1) The rock moves by uniformly accelerated motion, with constant acceleration $g=9.81 m/s^2$ . Its law of motion is given by $y(t)=h-v_0t-\frac{1}{2}gt^2$ , where $v_0=0$ is the initial velocity of the rock, and h is the height of the cliff. The time t1 is the time at which the rock reaches the ground, so that y(t1)=0, and the equation becomes
$0=h-\frac{1}{2}gt_1^2$
2) The sound moves from the ground to the top of the cliff by uniform motion, with constant speed v=343 m/s. Therefore, the sound covers the distance h (the height of the cliff) in a time t2 given by
$h=vt_2$
3) If we rewrite h in both equations, we can write:
$=\frac{1}{2}gt_1^2=vt_2$ (1)
4) We also know that the sum of t1 and t2 is equal to 10 seconds:
$t_1+t_2=10$
from which we find
$t_2=10-t_1$
if we substitute this into eq.(1), we get
$\frac{1}{2}gt_1^2+vt_1-10v=0$
Numerically:
$4.9t_1^2 + 343 t_1 - 3430=0$
Solving the equation, we find the solution $t_1=8.87 s$ (the other solution is negative, so it does not have physical meaning). As a consequence,
$t_2 = 10-t_1 = 1.13 s$
and the height of the cliff is given by
 $h=vt_2=(343 m/s)(1.13 s)=388 m$

3 0

2 years ago

Read 2 more answers

If the air temperature is the same as the temperature of your skin (about 30 ∘C), your body cannot get rid of heat by transferri

Neko [114]

Answer:

In That Case, It Gets Rid Of The Heat By Evaporating Water (sweat). During Bicycling, A Typical 72.0 Kgperson's Body Produces Energy At A Rate Of About 501 W Due To Metabolism ... If the air temperature is the same as the temperature of your skin (about 30 ∘C), your body cannot get rid of heat by transferring it to the air.

Explanation:

3 0

2 years ago

Read 2 more answers

Red Riding Hood sat down to rest and placed her 1.20-kg basket of goodies beside her. A wolf came along, spotted the basket, and

anygoal [31]

Answer:

117.6°

Explanation:

The vertical component of a force directed at some angle α from the vertical is ...

F·cos(α)

We want the vertical components of the wolf's force (Fw) and Red's force (Fr) to total zero. So for some angle from vertical α, Red's force will satisfy ...

Fw·cos(25°) + Fr·cos(α) = 0

cos(α) = -Fw/Fr·cos(25°) ≈ -(6.4 N)/(12.5 N)·0.906308 ≈ -0.464030

α ≈ arccos(-0.464030) ≈ 117.6°

Red was pulling at an angle of about 117.6° from the vertical.

_____

Additional comment

That's about 27.6° below the horizontal.

3 0

2 years ago

Frequency division multiplexing: A. operates by statistically time slicing the signal B. operates by dividing the signal into di

cestrela7 [59]

Frequency division multiplexing operates by dividing the signal into different frequencies

Explanation:

The technique that is used in the networking is the Frequency Division Multiplexing. using this technique, the existing bandwidths can be partitioned into different frequency bandwidths. These are not interrupting with each other. Each bandwidth can be used for carrying signals individually.

Using this technique many users can share a particular communication medium and they will not be interrupted with each other's communication.Hence this technique can also be termed as Frequency Division Multiple Access.

7 0

3 years ago

The electromagnetic wave that CT scans are based on is called a

kherson [118]

X-ray)
because Electromagnetic waves are in act

6 0

2 years ago