Mary walked north from her home to Sheila's home, which is 4.0 kilometers away. Then she turned right and walked another 3.0 kilometers to the supermarket, which is 5.0 kilometers from her own home. She walked the total distance in 1.5 hours. What were her average speed and average velocity?

Question

shamim · Answer

u know
average speed=total distance /time

shamim · Answer

average velocity=displacement /time

shamim · Answer

can u tell me
total distance =?

shamim · Answer

displacement =?

shamim · Answer

u know displacement  is a vector quantity

shamim · Answer

it has both magnitude n direction

shamim · Answer

but distance  has magnitude  only

shamim · Answer

n its a scalar quantity

osprey · Answer

she ended up 5km DISPLACEMENT from where she started. To get to that displacement, she walked a TOTAL DISTANCE of 7km (by the way, this seems to be a 3,,4, 5 right angled triangle) and she did this in 1.5 hours. So, her average speed was 7 divided by 1.5 km/hr which is sort of 7 divided by 3 times 2 or 14 divided by 3 or around about 4 km/hr which seems like a brisk walk ... I hope this is right, and I can see the poss for confusion ! http://perendis.webs.com