A packet is dropped from the window

  • Thread starter Aladin
  • Start date
  • Tags
    Window
In summary: So the packet goes upwards because of the force of the helicopter blades and the packet goes downwards because of the force of the air.In summary, the packet goes upward because of the force of the helicopter blades and goes downward because of the air.
  • #1
77
0
A helicopter is moving with some velocity in upward direction,a packet is dropped from the window of the helicopter.why the packet goes upward after dropping?What will be the velocity of the packet ?is its velocity is same as the helicopter?why,why?please explain.
 
Physics news on Phys.org
  • #2
Initially, the packet moves with the same velocity as the helicopter. Why would you think otherwise?
 
  • #3
When you drop an object from a stationary window, there is an instant during which your hand is no longer supporting it, but it has not yet started to fall. (In most real-world instances this moment is vanishingly brief but, in some cartoon situations it can last indeffinately, and largely deoends on how long it takes for the object to notice that it is unsupported.)

If you repeat the same process in a vehicle that is moving upwards, the object still has a tendency to remain "staionary" for an instant, but that means stationary relative to your hand, which means "moving upward" relative to the ground.
 
  • #4
Same idea as dropping something inside a train (similar to something in another thread). Although it drops straight down relative to the train, it describes a parabolic path relative to the ground.
 
  • #5
Oddly, the OP seems to think that, initially, the packet actually goes up.
 
  • #6
DaveC426913 said:
Oddly, the OP seems to think that, initially, the packet actually goes up.
Not so odd, since the helicopter is moving upward.
 
  • #7
Well,think of Newton's 1st law. The packet already has a velocity and will continue in that constant velocity. There will however, be external forces, air resistance and gravity which will pull it downwards. The reason the helicopter does not fall as well is that there is a force upwards exerted by the helicopter blades, well, making it able to fly in the first place.
 
  • #8
I am not understand please give me the reason that why the packet goes upward first.on the other hand the blades of helicopter are pushing air downward direction.then why the packet goes upward?
 
Last edited:
  • #9
True. But the air from the blades that pushes the packet down is a force. It CHANGES the velocity, not set the initial velocity. The initial velocity is set by the helicopter's velocity. In other words, it will keep on moving at that velocity since it is already moving upwards in the first place. Of course it will slow down and later fall but that is because of the existence of forces.
 

1. What factors determine how fast a packet will fall when dropped from a window?

The speed at which a packet falls from a window is determined by a few key factors such as its weight, air resistance, and the force of gravity. Heavier packets will generally fall faster than lighter ones, and the amount of air resistance will depend on the size and shape of the packet. Gravity, which pulls objects towards the Earth, also plays a significant role in determining the speed at which the packet falls.

2. How does air resistance affect a packet falling from a window?

Air resistance, also known as drag, is the force that opposes the motion of an object through the air. When a packet is dropped from a window, it will experience air resistance which will slow down its fall. This is because the air molecules are pushing against the packet and creating an upward force that counters the force of gravity pulling the packet downwards.

3. Will a packet always fall straight down when dropped from a window?

In most cases, a packet will fall straight down when dropped from a window. However, if there is wind or air currents present, the packet may be pushed or blown in a different direction, causing it to fall at an angle or even in a different direction altogether.

4. What happens to a packet when it reaches the ground after being dropped from a window?

When a packet reaches the ground after being dropped from a window, it will come to a stop. This is due to the force of gravity pulling the packet towards the Earth, which is balanced by the ground pushing back up on the packet with an equal and opposite force. The packet may also experience some deformation upon impact, depending on the material it is made of and the height from which it was dropped.

5. Can a packet be dropped from a window without falling?

No, a packet cannot be dropped from a window without falling. As long as the packet is within the Earth's gravitational field, it will experience a downwards force and will fall towards the ground. The only way to prevent a packet from falling would be to counteract the force of gravity with another force, such as a strong upward force from a rocket or parachute.

Similar threads

  • Introductory Physics Homework Help
2
Replies
69
Views
10K
  • Introductory Physics Homework Help
Replies
25
Views
338
  • Introductory Physics Homework Help
2
Replies
39
Views
2K
  • Introductory Physics Homework Help
Replies
10
Views
4K
  • Introductory Physics Homework Help
Replies
7
Views
2K
  • Computing and Technology
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
34
Views
473
  • Introductory Physics Homework Help
Replies
7
Views
2K
  • Quantum Physics
Replies
1
Views
581
Back
Top