# Need help- AS physics questions.Watch

#1
Hi, I’m trying to complete some questions in preparation for my Physics mock.

“A bus is moving along a busy road at constant speed. A child throws its dummy out of one of the bus windows. A pedestrian on the pavement sees the dummy. Ignoring air resistance:

Describe the horizontal motion of the dummy observed by the pedestrian Describe the horizontal motion of the dummy observed by the child

Now, consider that air resistance is acting.

Describe the horizontal motion of the dummy observed by the pedestrian Describe the horizontal motion of the dummy observed by the child”

Any help would be greatly appreciated!
0
1 year ago
#2
Ignoring air resistance:
For the child, there's no horizontal motion, the dummy just fall straight down. This is similar to when she drop her dummy inside the bus.
For the pedestrian, the horizontal motion of the dummy is similar to that of the bus (with the same constant speed)

With resistance:
The child will see the dummy going back, because there's a net force act on the dummy (for the bus, air resistance and driven force of motor balance).
The pedestrian will see the dummy travel at a speed lower than that of the train. The speed of dummy will decrease and finally it will stop because the only force acting on it is the air resistance (provided that the vertical height is big enough)

Probably too long but that's what I think.
0
#3
Thankyou!!!
0
X

new posts
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### University open days

• Birkbeck, University of London
Thu, 21 Mar '19
• University of Wolverhampton
Thu, 21 Mar '19
• Edge Hill University
Fri, 22 Mar '19

### Poll

Join the discussion

#### Where do you need more help?

Which Uni should I go to? (64)
15.42%
How successful will I become if I take my planned subjects? (42)
10.12%
How happy will I be if I take this career? (78)
18.8%
How do I achieve my dream Uni placement? (60)
14.46%
What should I study to achieve my dream career? (45)
10.84%
How can I be the best version of myself? (126)
30.36%