Vry simple objective questions

[ritwik06]

To which class do the following levers belong to?
1. Motor car foot brake? My ans. is it class 1?
2. Opening a box. My ans: seems to be class 2 type.

State the energy changes that occur in:
a loaded truck when started and set in motion.
It seems to me that it would be Chemical energy of fuel to kinetic energy. but my teacher says potential energy to kinetic energy.

 

[Stevedye56]

You would have chemical potential energy in the gas, which is then converted into kinetic energy upon combustion.

 

[ritwik06]

You would have chemical potential energy in the gas, which is then converted into kinetic energy upon combustion.

thanks for the answer. Can you please comment on the first??

 

[Stevedye56]

thanks for the answer. Can you please comment on the first??

What do you mean comment on the first? If you mean to ask what lever class they fall under, I though it was explanied in the website. Maybe not though.

Edit: Sorry I thought that this was a thread I had replied to earlier, and therefore the link was not posted. My appoligies. Here is the link.

http://www.technologystudent.com/forcmom/lever1.htm

 

[ritwik06]

What do you mean comment on the first? If you mean to ask what lever class they fall under, I though it was explanied in the website. Maybe not though.

Edit: Sorry I thought that this was a thread I had replied to earlier, and therefore the link was not posted. My appoligies. Here is the link.

http://www.technologystudent.com/forcmom/lever1.htm

its ok! but I already know about levers. I have guessed the answers as well. please do tell me if i am right.

And yes, the case is of a "motor car" "foot" brake!