No, if the car were moving sideways, then the forces used would be on the horizontal axis. So the weight equation would be extraneous, unless one is determining the net force through an inclined plane

7 0

3 years ago

The Bullet Train The Shinkansen, the Japanese "bullet" train, runs at high speed from Tokyo to Nagoya. Riding on the Shinkansen,

jeyben [28]

Answer:

68.6 m/s

Explanation:

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

u = Speed of train

$f_1$ = Actual frequency

From the Doppler effect we have the observed frequency as

When the train is approaching

$f=f_1\frac{v+u}{v}$

When the train is receeding

$\frac{2f}{3}=f_1\frac{v-u}{v}$

Dividing the above equations we have

$\frac{f}{\frac{2f}{3}}=\frac{f_1\frac{v+u}{v}}{f_1\frac{v-u}{v}}\\\Rightarrow \frac{3}{2}=\frac{v+u}{v-u}\\\Rightarrow 3v-3u=2v+2u\\\Rightarrow v=5u\\\Rightarrow u=\frac{v}{5}\\\Rightarrow u=\frac{343}{5}\\\Rightarrow u=68.6\ m/s$

The speed of the train is 68.6 m/s

5 0

3 years ago

15. What is a thermograph?

Genrish500 [490]

Answer: A device that uses infrared sensors.

Explanation:

8 0

3 years ago

Read 2 more answers

PLLLLLLLLLZ HELP 30 POINTS ANSWER ONLY IF YOU KNOW

Karo-lina-s [1.5K]

Answer:

R^2 = 40^2 + 70^2 - 2(40)(70) cos 135°

Explanation:

The resultant connects the tail of the first vector to the head of the second vector (whose tail is at the head of the first vector). The three vectors form an obtuse triangle where the angle between the original direction and the second direction is 135°. The cosine factor in the Law of Cosines formula will be cos(135°), matching the second choice.

4 0

3 years ago