#2 plz help this is due tomorrow

Two cars approaching each other , first car moves at 72 km/h ,the second car moves at 90 km/h,the first car started its siren wi

Iteru [2.4K]

Answer:

Because the speed of sound travels at +- 1300 km/h and the car that is approaching isn't that fast. So u first hear the sound before the car reaches u.

i hope it helps

Explanation:

6 0

3 years ago

Read 2 more answers

Which statements best describe the atoms of the gas neon? Check all that apply.

Anni [7]

What are the statements?

5 0

3 years ago

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State and explain the principle of superposition of electrostatic force

ella [17]

Answer:

The principle of superposition states that when a number of charges are interacting, the net electrostatic force a given charge is the vector sum of the forces exerted on it due to all other charges. The force between two charges is not affected by the presence of other charges.

8 0

3 years ago

how long would it take a 3.4 kg bike with 79 kg rider traveling at 18.6 m/s to stop if 867 N of force is applied to the brakes?

nalin [4]

Answer: 1.76 s

Explanation:

We have the following data:

$m=3.4 kg+79 kg=82.4 kg$ is the total mass of the bike and the rider

$V_{o}=18.6 m/s$ is the initial velocity

$F=867 N$ is the force applied to the brakes

Firstly, we will find the acceleration $a$ with the following equation:

$F=m.a$ (1)

Isolating $a$ :

$a=\frac{F}{m}$ (2)

$a=\frac{867 N}{82.4 kg}$ (3)

$a=10.52 m/s^{2}$ (4) This is the magnitude of the acceleration, however, since the final velocity is 0 m/s, this means the direction is negative

Hence:

$a=-10.52 m/s^{2}$ (5)

On the other hand, with the following equation we can find the time $t$ :

$V=V_{o}+at$ (6)

Where:

$V=0 m/s$ is the final velocity (the bike stops)

Isolating $t$ :

$t=-\frac{V_{o}}{a}$ (7)

$t=-\frac{18.6 m/s}{-10.52 m/s^{2}}$ (8)

Finally:

$t=1.76 s$ This iste time it takes to the bike to stop

7 0

3 years ago

Twoâ€‹ high-speed ferries leave at the same time from a city to go to the same island. The firstâ€‹ ferry, theâ€‹ Cat, travels a

kumpel [21]

Answer:

1 hour

Explanation:

Since the definition of velocity is $v=x/t$ , we can calculate the position at time t of an object moving at speed v with $x=vt$ .

The position of the first ferry is $x_1=v_1t$

The position of the second ferry is $x_2=v_2t$

We want to know when they will be 6 miles apart. This means, if we call that distance d, that we want to know when the difference between their positions will be d, or $x_1-x_2=d$ (we know that at the beginning the position of the ferry 1 is of higher value than that of ferry 2 since it left before).

We use our previous formulas then:

$d=x_1-x_2=v_1t-v_2t=(v_1-v_2)t$

Since we want the time, we do:

$t=\frac{d}{v_1-v_2}$

And substitute our values:

$t=\frac{6\ miles}{30\ miles/hour-24\ miles/hour}=\frac{6\ miles}{6\ miles/hour} =1\ hour$

7 0

3 years ago