1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
kenny6666 [7]
3 years ago
14

A circular jogging track forms the edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track

at the average rate of 3 miles per hour. If t represents the number of hours it took Johanna to walk completely around the lake, which of the following is a correct statement?(A) 0.5< t < 0.75 (B) 1.75< t < 2.0 (C) 2.0 < t < 2.5 (D) 2.5 < t < 3.0 (E) 3 < t < 3.5
Physics
1 answer:
Taya2010 [7]3 years ago
7 0

Answer:

The number of hours is 2.1.

(c) is a correct statement.

Explanation:

Given that,

Diameter = 2 miles

Average rate = 3 miles/hr

We need to calculate the time

Using formula of average rate

Average\ rate =\dfrac{Total\ distance}{Total\ time}

Put the value into the formula

3=\dfrac{2\pi\times r}{t}

t=\dfrac{6.28}{3}

t = 2.1\ hr

2.1 lies between 2.0 and 2.5.

Hence, The number of hours is 2.1.

You might be interested in
A 1.11 kg piece of aluminum at 78.3 c is put into a glass with 0.210 kg of water at 15.0
ValentinkaMS [17]

M = mass of aluminium = 1.11 kg

c_{a} = specific heat of aluminium = 900

T_{ai} = initial temperature of aluminium = 78.3 c

m = mass of water = 0.210 kg

c_{w} = specific heat of water = 4186

T_{wi} = initial temperature of water = 15 c

T = final equilibrium temperature = ?

using conservation of heat

Heat lost by aluminium = heat gained by water

M c_{a} (T_{ai} - T) = m c_{w} (T - T_{wi} )

(1.11) (900) (78.3 - T) = (0.210) (4186) (T - 15)

T = 48.7 c

7 0
3 years ago
Which factors affect heat transfer between a warm and a cool substance?
damaskus [11]
Factors that affect heat transfer are:

1) Difference in temperature, 
2) Mass of the object
3) Specific heat of the object

Hope this helps!
8 0
3 years ago
Help please
Anarel [89]

Answer:

1) D, 2) D, 3) B, 4) B, 5) C

Explanation:

You are asked to select the correct answer

1)  The conservation of energy is one of the most important principles of physics that allows solving countless problems in life.

the correct answer is D

2) when a body falls, the gravitational potential energy is transformed into kinetic energy and both are transformed into thermal energy

the correct answer is D

3) When the gravitational potential energy is maximum, the kinetic energy is minimum and when the kinetic energy is maximum, the gravitational energy is minimum.

Correct answer B

4) speed is defined by

         v = x / t

so the correct answer is B in the SI system

5) when we repeat a measurement several times, the random or statistical errors decrease, therefore the confidence of the measurement increases.

The correct answer is C

4 0
3 years ago
A learner sets up a circuit to determine the conductivity of certain solids. What piece of apparatus is not required for the nex
Lilit [14]
It is D as u dont need a stop watch aft that
4 0
3 years ago
Which statement correctly describes a characteristic that a scientific measuring tool should have
Reil [10]

Explanation:

To be accurate, it must be able to make measurements that are close to the actual value.

6 0
3 years ago
Other questions:
  • If different groups of scientist have access to the same data, how can they draw different conclusions?
    5·1 answer
  • A rubber ball with a mass of 0.30 kg is dropped onto a steel plate. The ball's velocity just before impact is 4.5 m/s and just a
    7·1 answer
  • A helicopter lifts a 66 kg astronaut 15 m vertically from the ocean by means of a cable. The acceleration of the astronaut is g/
    7·1 answer
  • A ball whose mass is 1.9 kg is suspended from a spring whose stiffness is 8.0 N/m. The ball oscillates up and down with an ampli
    10·1 answer
  • Which of these is another name for Newton's
    10·2 answers
  • Is the system in the image moving? Explain. If it is moving, find its acceleration.
    6·1 answer
  • PLEASE HELP WITH THE 6 FOLLOWING SCIENCE QUESTIONS (the topic is circuit symbols and equations):
    5·1 answer
  • describe the forces acting on a car as it movies along a level highway in still air at a constant speed
    7·1 answer
  • How to install goodman heat pump with ducting apartment
    13·1 answer
  • Question 20 (4 points)
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!