All categories

3 years ago

1. A sprinter races in the 100 meter dash. It takes him 10 second to reach the finish line

Physics

1 answer:

poizon [28]3 years ago

6 0

Answer:

v = 10 m/s

Explanation:

Given that,

Distance covered by a sprinter, d = 100 m

Time taken by him to reach the finish line, t = 10 s

We need to find his average velocity. We know that velocity is equal to the distance covered divided by time taken. So,

v = d/t

$v=\dfrac{100\ m}{10\ s}\\\\v=10\ m/s$

Hence, his average velocity is 10 m/s.

You might be interested in

Particle moves in a circle of radius 90m with a constant speed 25m/s. how many revolution does it make in 30sec

Serggg [28]

Answer:

n =1.33 revolutions

Explanation:

Uniform Circular Motion

The angular speed can be calculated in two different ways:

$\displaystyle \omega=\frac{v}{r}$

Where:

v = tangential speed

r = radius of the circle described by the rotating object

Also:

$\omega=2\pi f$

Where:

f = frequency

Solving for f:

$\displaystyle f=\frac{\omega}{2\pi}$

Since the frequency is calculated when the number of revolutions n and the time t are known:

$\displaystyle f=\frac{n}{t}$

We can solve for n:

n=f.t

The particle moves in a circle of r=90 m with a speed v=25 m/s. Thus the angular speed is:

$\displaystyle \omega=\frac{25}{90}$

$\displaystyle \omega=0.278\ rad/s$

Now we calculate f:

$\displaystyle f=\frac{0.278}{2\pi}$

$f=0.04421\ Hz$

Calculating the number of revolutions:

n = 0.04421*30

n =1.33 revolutions

8 0

3 years ago

Peter, a 100 kg basketball player, lands on his feet after completing a slam dunk and then immediately jumps up again to celebra

Mars2501 [29]

Answer:

Explanation:

Impulse = change in momentum

Initial momentum = mass x initial velocity = 100 x 5 = 500 kg m/s

final momentum = mass x final velocity = 100 x - 4 = -400 ( - ve sign due to reversal of direction )

change in momentum = final momentum - initial momentum

= - 400 - 500 = - 900 kg m/s .

As it is - ve , it acts upwards .

So magnitude of impulse on Perter = 900 kg m/s

4 0

3 years ago

An automobile is traveling on a long, straight highway at a steady 80.0 mi/h when the driver sees a wreck 190 m ahead. At that i

kozerog [31]

Answer:

a) The car’s speed just after leaving the icy portion of the road is the first part

Explanation:

6 0

3 years ago

.A formula that contains 2 elements is called a.

mr Goodwill [35]

Answer:

I think it is H2O . Formula of water

4 0

3 years ago

[4 marks] 22. Compare and contrast the structure and roles of tendons and ligaments.

sladkih [1.3K]

Answer:

Tendons: Tendons are cord-like, strong, inelastic structures that join skeletal muscles to bones

ligaments: Ligaments are elastic structures which connect bones to bones in joints.

Explanation:

6 0

3 years ago