Mr. g i running down the street trying to catch the bus. he is one city block away (200m) and this bus is leaving in 10s.

a) how fast does mr. g need to run to catch the bus on time? (hint: what do you know about the problem)

b) if the fastest human can run 12 m/s, will mr. g be able to catch the bus? explain your answer

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j ?

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? question 2 options: the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the cold balloon expands and rises. the warm balloon shrinks and sinks. the warm balloon expands and rises. the cold balloon shrinks and sinks.

Which of the following is not a physical property of mattera. melting pointb.heat of combustionc. viscosityd. boiling point