Plz help , qucik plz.. Give the direction of the net force acting on each of the following objects.?

2009-03-13 5:42 am
I already did it, just want some one to check...
Give the direction of the net force acting on each of the following objects. If the net force is zeros, state "zero".
a) A car accelerating northward from a stop light. Northward
b)A car traveling southward and slowing down. Northward
c) a car traveling west with a constant speed. zero
d) A skydiver parachuting downwards at terminal velocity. Zero
e) A baseball during its flight from pitcher to catcher (ignore air resistance) Right, ( i just guessing)
If i am wrong, plz explain it to me , ty :)

回答 (3)

2009-03-13 6:35 am
✔ 最佳答案
All of your answers are correct except the last one.

For e) a baseball during its flight from pitcher to catcher, ignoring air resistance, you need to think of the following:

Since we are ignoring air resistance, there is no force acting horizontally on the ball (at least until it hits either the bat or the catcher's mitt - but nothing during its flight). However, the force of gravity is acting on the ball. Therefore, the net force on the ball is downward.

(The other examples all had a downward force of gravity acting on them as well, but in those cases that downward force was countered by an opposing force of equal magnitude so there was no vertical component of force remaining. The ball does not have that opposing vertical force.)
2009-03-13 5:55 am
e

im doing that same lession in school! lol
2009-03-13 5:53 am
e.) since no direction is given, you usually use "forwards" or "backwards" unless there's a diagram we're not seeing here.. O.o

or if you want to be specific "towards ___"


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