No products in the cart.

A car travel 30 km at …

CBSE, JEE, NEET, CUET

CBSE, JEE, NEET, CUET

Question Bank, Mock Tests, Exam Papers

NCERT Solutions, Sample Papers, Notes, Videos

A car travel 30 km at a uniform speed of 40 km/h and the next 30 km at a uniform speed of 20 km/h. Find its average speed

Posted by Anshika Kumari 4 years, 4 months ago

CBSE > Class 09 > Science

3 answers

Aadarsh Chowdhary 4 years, 4 months ago

We know that, Speed=Distance / time .°. Time =dist / speed Let's see the first case, s = distance = 30 km v = speed = 40 km/hr t = time = 30 / 40 =3/4 hrs Let's see the second case, s = 30 km v = 20 km/hr t = 30 / 20 t = 3/2 hrs Avg. Speed =Total distance/ Total time =(30 + 30) / (3/4) + (3/2) =60 / ( 3 + 6 ) /4 =60 / 9 × 4 =20 / 3 × 4 =80 / 3 =26.67 ( Approx. ) Hence, Average speed of the car is 26.67 km/hrs ( Approx).

Yogita Ingle 4 years, 4 months ago

Given that ,
    1st 30 km uniform speed is (u1) = 40 km/h
     2nd 30 km uniform speed is ( u2 ) = 20 km/h
     total distance ( d ) = 30 + 30 = 60 km
     time taken in 1st time = d / t = 30/40 also, 3h / 4 = 180/4 = 45 min
     time taken in 2nd time = d/t = 30/20 also, 3h/2 = 180/2 = 90 min
    total time = 45 + 90 = 135 min = 135/60 h
average speed = 60/135/60 = 60 * 60 /135 = 26.66 km/h

Prithviraj Talikoti 4 years, 4 months ago

The average speed of car is 26.67km/h

ANSWER

http://mycbseguide.com/examin8/

Related Questions

A boxer moves his head backward when his opponent blows a punch.

Posted by Prasanna Mendon 2 months, 1 week ago

CBSE > Class 09 > Science

1 answers

This content has been hidden. One or more users have flagged this content as inappropriate. Once content is flagged, it is hidden from users and is reviewed by myCBSEguide team against our Community Guidelines. If content is found in violation, the user posting this content will be banned for 30 days from using Homework help section. Suspended users will receive error while adding question or answer. Question comments have also been disabled. Read community guidelines at https://mycbseguide.com/community-guidelines.html

Few rules to keep homework help section safe, clean and informative.

Don't post personal information, mobile numbers and other details.
Don't use this platform for chatting, social networking and making friends. This platform is meant only for asking subject specific and study related questions.
Be nice and polite and avoid rude and abusive language. Avoid inappropriate language and attention, vulgar terms and anything sexually suggestive. Avoid harassment and bullying.
Ask specific question which are clear and concise.

Remember the goal of this website is to share knowledge and learn from each other. Ask questions and help others by answering questions.

Posted by Abhi Sandhu 2 months, 1 week ago

CBSE > Class 09 > Science

1 answers

What are the parts of a flower

Posted by Op Garg 2 months, 2 weeks ago

CBSE > Class 09 > Science

2 answers

WHAT IS UNIT OF LIFE

Posted by Yash Dwivedi 2 months, 2 weeks ago

CBSE > Class 09 > Science

3 answers

Why is it advised to tie any luggage kept on the roof of a bus with a rope ?

Posted by Huda Fatima 2 months, 2 weeks ago

CBSE > Class 09 > Science

2 answers

Define speed and velocity provide one similarity and one difference between them

Posted by Himanshi Sharma 2 months, 2 weeks ago

CBSE > Class 09 > Science

0 answers

What is ER??

Posted by Maitri Patel 2 months, 3 weeks ago

CBSE > Class 09 > Science

1 answers

Assertion:Sun appears to rise in the east and set in the west Reason:The earth revolves around the sun in uniform circular motion

Posted by Tejal Sawant 2 months, 3 weeks ago

CBSE > Class 09 > Science

3 answers

This content has been hidden. One or more users have flagged this content as inappropriate. Once content is flagged, it is hidden from users and is reviewed by myCBSEguide team against our Community Guidelines. If content is found in violation, the user posting this content will be banned for 30 days from using Homework help section. Suspended users will receive error while adding question or answer. Question comments have also been disabled. Read community guidelines at https://mycbseguide.com/community-guidelines.html

Few rules to keep homework help section safe, clean and informative.

Don't post personal information, mobile numbers and other details.
Don't use this platform for chatting, social networking and making friends. This platform is meant only for asking subject specific and study related questions.
Be nice and polite and avoid rude and abusive language. Avoid inappropriate language and attention, vulgar terms and anything sexually suggestive. Avoid harassment and bullying.
Ask specific question which are clear and concise.

Remember the goal of this website is to share knowledge and learn from each other. Ask questions and help others by answering questions.

Posted by Samir Chakma 1 month, 1 week ago

CBSE > Class 09 > Science

0 answers

If one mole of carbon atoms weighs 12 grams, what is the mass (in grams) of 1 atom of carbon?

Posted by Anmol Kumar 2 months, 2 weeks ago

CBSE > Class 09 > Science

0 answers

myCBSEguide App

myCBSEguide

Trusted by 1 Crore+ Students

Test Generator

Test Generator

Create papers online. It's FREE.

CUET Mock Tests

CUET Mock Tests

75,000+ questions to practice only on myCBSEguide app

Google Play

Download myCBSEguide App