Again, I say help if you want and if you have a heart! I tried answering some of these but I have a "poor" PHysics teacher.I have straight A's and 1 B in that class. So, I know it's her not me b/c everyone in her class is failing!!!
17. A projectile is fired at some angle to the horizontal w/ some initial pseed v0, & air resistance is neglected. Is the projectile a freely falling body? What is its acceleration in the vertical direction? What is its acceleration in the horizontal direction?
2. (a) an object has only 1 force acting on it. Can it be at rest? (yes maybe) Can it have accleration (idk) (B) An object has 0 acc. Does this mean that no forces act on it?
3. Is it possible for an obj. to move if no net force acts on it? (No - I think)?
9. In the motion pic IT HAPPENED ONE NIGHT Clark G. is standing inside a sationary bus in front of Claudette Colbert, who is seated. The bus suddenly starts moving forward & clark falls into Claud.s lap. Y did this happen?
2006-12-13 10:52:26 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
# 17. Yes it is free falling because only gravity is affecting it. Acceleration in the y-axis is -9.8 m/s^2 the "g" constant. No horizontal acceleration.
#2. No, cannot be at rest because the Net force will not be 0. Yes it can have acceleration.
0 acceleration does NOT mean no forces, if the forces are equal and opposite than it will move at a constant speed or not move at all.
#3. Only if it is already in motion.
#9. Because his body wanted to stay at rest while the bus started moving. So if you are outside the bus, you would not see his position change but the bus did. I.e. If he was directly over a manhole, than after he falls he would still be relativly above the manhole. While the seated guy was pushed by his seat forward.
2006-12-13 11:21:11 · answer #1 · answered by adklsjfklsdj 6 · 0⤊ 0⤋
i don't like projectile motion plus i don't have a calculator right now so i'm avoiding that one...
2 a) well it all depends if you have the object that is falling down a slope and there is an opposite force that makes it stop then it can be at rest... but if there is a force then that means that there must be an acceleration so i think that they want to to say that it can't be at rest
b) i basically said it previosly, acceleration=force acting on the object, 0 acceleration 0 force
3) yes it is possible newton's first law-> everything that is moving will keep moving unless there is a force that oppose it or something like that, the point is that is can be al ready moving and there is no force acting on it... think about it in the space a spaceship doesn't need any force to make it move once it's in space
9) once more newton's lovely laws objects tend to keep moving if they are moving or be still if they are still, Clark's body tended to stay in the place where he was but suddenly the bus moved and there was the force of his body trying to make him stayed where he was that pushed him back
(it's not actually the force of his body what made him stay but i just stated it like that to make it more clear)
2006-12-13 19:05:40 · answer #2 · answered by enani 1 · 0⤊ 0⤋
17. yes, free falling.
@=angle from horizon
Av=(Vo(sin@)) - 9.8m/s2
Ah=no accel, only velocity since resist is neglected
Vh=(Vo(cos@))
2.(a) if no friction, NO. If friction is considered, YES. Again, if no friction, then yes. But, if otherwise, NO.
(b) NO it doesnt
3.No
9. Momentum of bus is greater than Clark's. When momentum changed, it moved him.
2006-12-13 19:14:01 · answer #3 · answered by jpferrierjr 4 · 0⤊ 0⤋
it bcomes a freely falling obj the moment its initial velocity bcomes 0.
clark----due to inertia, he has a tendency to continue in his prev position(newtons law)
2006-12-13 19:28:02 · answer #4 · answered by calmserene 4 · 0⤊ 0⤋