What should #1 be labeled?

At the Indianapolis 500, you can measure the speed of cars just by listening to the difference in pitch of the engine noise betw

allsm [11]

To develop this problem it is necessary to apply the concepts related to the Dopler effect.

The equation is defined by

$f_i = f_0 \frac{c}{c+v}$

Where

$f_h$ = Approaching velocities

$f_i$ = Receding velocities

c = Speed of sound

v = Emitter speed

And

$f_h = f_0 \frac{c}{c+v}$

Therefore using the values given we can find the velocity through,

$\frac{f_h}{f_0}=\frac{c-v}{c+v}$

$v = c(\frac{f_h-f_i}{f_h+f_i})$

Assuming the ratio above, we can use any f_h and f_i with the ratio 2.4 to 1

$v = 353(\frac{2.4-1}{2.4+1})$

$v = 145.35m/s$

Therefore the cars goes to 145.3m/s

7 0

3 years ago

Doctors use the radioactive isotope chromium-51 to label red blood cells in the human body. Chromium-51 gives off relatively ___

dimaraw [331]

harmless, a sheet of paper
Alpha particles do not possess a high amount of energy and are not very ionizing, since they have a high mass. This makes them relatively safer to work with.

6 0

3 years ago

Read 2 more answers

A horse is working steadily, providing 750 W of output power. How much food energy does the horse need to work for 1 hour, to th

Valentin [98]

Answer:

Under assumption that all food energy that needs the horse is transformed into work, then the horse needs approximately 3 megajoules of food energy to work for 1 hour.

Explanation:

Since horse is working steadily, the power experimented by the horse ( $\dot W$ ), measured in watts, is at constant rate. Then, the work needed by the horse ( $W$ ), measured in joules, is equal to that power multiplied by time ( $\Delta t$ ), measured in seconds. That is:

$W = \dot W\cdot \Delta t$ (1)

If we know that $\dot W = 750\,W$ and $\Delta t = 3600\,s$ , then the work needed for the horse is:

$W = (750\,W)\cdot (3600\,s)$

$W = 2.7\times 10^{6}\,J$

$W = 2.7\,MJ$

Under assumption that all food energy that needs the horse is transformed into work, then the horse needs approximately 3 megajoules of food energy to work for 1 hour.

7 0

3 years ago

Why do scientists need a standard system of measurement?

djyliett [7]

The answer is so that everyone is measuring the same distance and counting that distance as the same everywhere. one example from real life why it is important to use standard units is the loss of the NASA mars orbiter. some people decided that the units were to be in metric and others thought that the units were in imperial (english) system. so the orbiter was lost.

let's eliminate some choices
A. to allow for consistientcy with measurement data:
not really, just make sure the instruments are accurate.

B. to use tools marked in customary units: this could be true because a custom is something that is accepted in a wide area and if it is standard, then it is customary so b is the answer

C. so they can keep measurement data secret: nope

D. to record with easier abbreviations: not really

the answer is B

7 0

3 years ago

Read 2 more answers

A 10 kg box accelerates for at a rate of 12 miles per second what is the force acting on the box

lions [1.4K]

193080N

Explanation:

Given parameters:

Mass of the box = 10kg

Acceleration = 12miles per second

Unknown:

Force on the box = ?