All categories

3 years ago

Someone help please.....

Physics

1 answer:

Westkost [7]3 years ago

8 0

Answer:

0.0928km/min (4dp)

Explanation:

To find the jogger's speed in km per minute, we just need to divide the number of km jogged by the time in minutes it took to jog that distance. This will give us the distance they jogged every minute which is their speed.

4km in 32 minutes:

4/32 = 0.125km/min

2km in 22 minutes:

2/22 = 0.091 (3dp)km/min

1km in 16 minutes:

0.0625km/min

Now to find the average speed of these 3 speeds, we just add them all together and divide by how many values there are (3 values).

Average (mean) = $\frac{0.125+0.091+0.0625}{3}$

Average = 0.2785/3

Average speed of jogger = 0.0928 (4dp) km/min

Hope this helped!

You might be interested in

A science teacher ran a marathon. After the race she showed her students the silver blanket she was given to keep her warm.A gro

spin [16.1K]

Answer:

the foiley like color doesn't absorb the heat it bounces off of it. it would be much better to have a black blanket

7 0

3 years ago

A resonance tube can be used to measured the speed of sound in air. A tuning fork is held above the opening of the tube and stru

LenaWriter [7]

Answer:

330.24 Hz

Explanation:

Given:

Frequency, f = 320 Hz

L1 = 25.8 cm

L2 = 78.4 cm

L3 = 131.1 cm

Let the wavelength be λ

Then, L1 which is the length of the column of air is λ/4.

λ/4 = 25.8 cm

λ = 25.8 × 4 = 103.2 cm = 1.032 m

Then, speed of sound in air is:

v = λ f

⇒ v = 1.032 × 320 Hz

⇒ v = 330.24 m/s

7 0

3 years ago

A soccer ball with mass 0.450 kg is initially moving with speed 2.20 m/s. A soccer player kicks the ball, exerting a constant fo

Alinara [238K]

Answer:

0.187 m

Explanation:

We'll begin by calculating the acceleration of the ball. This can be obtained as follow:

Mass (m) = 0.450 Kg

Force (F) = 38 N

Acceleration (a) =?

F = m × a

38 = 0.450 × a

Divide both side by 0.450

a = 38 / 0.450

a = 84.44 m/s²

Finally, we shall determine the distance. This can be obtained as follow:

Initial velocity (u) = 2.20 m/s.

Final velocity (v) = 6 m/s

Acceleration (a) = 84.44 m/s²

Distance (s) =?

v² = u² + 2as

6² = 2.2² + (2 × 84.44 × s)

36 = 4.4 + 168.88s

Collect like terms

36 – 4.84 = 168.88s

31.52 = 168.88s

Divide both side by 168.88

s = 31.52 / 168.88

s = 0.187 m

Thus, the distance is 0.187 m

6 0

3 years ago

In a simple machine, the energy input is 120 J. If the efficiency of the machine is 80%, calculate the energy output

pashok25 [27]

Answer:

<h2>96 Joules</h2>

Explanation:

We know that efficiency is the ratio of output power by input power. i.e. Efficiency describes the quality of machine or system how good it is.

Solution,

Energy input of system = 120 J

Efficiency = 80% = $\frac{80}{100} = 0.8$

Now,

According to definition,

Efficiency = $\frac{output}{input}$

Cross multiplication:

$output \: = \: 0.8 \times 120$

Calculate the product

$output \: = 96 \: joules$

Hope this helps...

Good luck on your assignment...

4 0

3 years ago

An electrician wraps rubber electrical tape around a copper wire. Since rubber is an insulator, which statement best explains th

yuradex [85]

A) Rubber stops charges from flowing. This protects people by stopping electricity from flowing.

Explanation:

The statement that best describes the point of wrapping rubber around the copper wire is that the rubber stops charges from flowing. This prevents people from getting electrical shocks by stopping the flow of electricity.

A rubber is an insulator.
Insulators are substances that prevents the flow of electricity.
The lack free mobile electrons or ions that makes them conductors.
When they are wrapped round a conductor such as copper wire, they will halt the flow of charges.
Copper is a conductor of both heat and electricity. It has free mobile electrons.

learn more:

Metals brainly.com/question/2474874

#learnwithBrainly

4 0

4 years ago