All categories

2 years ago

A race car circles 10 times around a circle with a diameter of 7 km track in 50 min. Using SI

Physics

1 answer:

vodka [1.7K]2 years ago

4 0

Average Speed = 23.33 m/s

<u>Explanation:</u>

Given:

Diameter = 7 km

So, to find the distance, we need to multiply it by 10 as the race car circles 10 times round this 7 km track.

Distance = 7 × 10 = 70 Km or 70,000 m

Time = 50 mins

= 50 × 60 = 3000 s

Now, in order to find the average speed for 10 cycles, we use the formula:

$Speed = \frac {Distance} {Time}$

So by substituting the above values in the given formula, we get:

$Speed = \frac {70,000} {3000}$

Speed = 23.33 m/s

You might be interested in

What is the atmospheric pressure 1.00 km above the surface of Venus? Express your answer in Earth-atmospheres.

EleoNora [17]

Below is an attachment containing the solution.

4 0

2 years ago

A) A spaceship passes you at a speed of 0.800c. You measure its length to be 31.2 m .How long would it be when at rest?

rosijanka [135]

Answer:

$l_o =52 \ m$

$l = 37.13 \ LY$

Explanation:

From the question we are told that

The speed of the spaceship is $v = 0.800c$

Here c is the speed of light with value $c = 3.0*10^{8} \ m/s$

The length is $l = 31.2 \ m$

The distance of the star for earth is $d = 145 \ light \ years$

The speed is $v_s = 2.90 *10^{8}$

Generally the from the length contraction equation we have that

$l = l_o \sqrt{1 -[\frac{v}{c } ]}$

Now the when at rest the length is $l_o$

$l_o =\frac{l}{\sqrt{ 1 - \frac{v^2}{c^2 } } }$

$l_o =\frac{ 31.2 }{ \sqrt{1 - \frac{(0.800c ) ^2}{c^2} } }$

$l_o=52 \ m$

Considering b

Applying above equation

$l =l_o \sqrt{1 - [\frac{v}{c } ]}$

Here $l_o =145 \ LY(light \ years )$

$l=145 * \sqrt{1 - \frac{v_s^2}{c^2 } }$

$l =145 * \sqrt{ 1 - \frac{2.9 *10^{8}}{3.0*10^{8}} }$

$l = 37.13 \ LY$

4 0

2 years ago

How much total surface of the moon is illuminated by the sun when it is at quarter phase?

alex41 [277]

50% of the moon is always illuminated, however during it's quarter phase means that we only see a quarter of what's really lit up. So it LOOKS like the moon is only 25% lit and 75% dark, it's truly 50/50. We only see that 25% since we can see it from one angle.

6 0

2 years ago

1.- Un barco recorre la distancia que separa Gran Canaria de Tenerife (90 km) en 6 horas. ¿Cuál es

bezimeni [28]

Answer:

The speed is 15 km/h or 4.16 m/s.

Explanation:

A boat travels the distance that separates Gran Canaria from Tenerife (90 km) in 6 hours. Which the speed of the boat in km / h? And in m / s?

Given that,

Distance, d = 90 km = 90000 m

Time, t = 6 hours = 21600 s

Speed = distance/time

$v=\dfrac{90\ km}{6\ h}\\\\=15\ km/h$

$v=\dfrac{90000\ m}{21600\ s}\\\\=4.16\ m/s$

So, the required speed is 15 km/h or 4.16 m/s.

7 0

2 years ago

11. Explain why in terms of gravity and air resistance and the 2nd law, objects in free fall regardless of mass hit at the same

Alchen [17]

Answer:

When an object is dropped, it accelerates toward the center of Earth. Newton's second law states that a net force on an object is responsible for its acceleration. If air resistance is negligible, the net force on a falling object is the gravitational force.

7 0

2 years ago