An object accelerates at 20 m/s2. By how much does the speed change in one second?

A student is trying to determine the acceleration of a feather as she drops it to the ground. if the student is looking to achie

Anna [14]

The coordinate system should have the origin at the point where the feather is dropped and the downward direction is to be taken as positive.

All falling bodies experience acceleration towards the center of the Earth due to the force of gravitational attraction exerted on the object by the Earth. A feather, when dropped experiences an acceleration in the downward direction. Since the acceleration of the feather is in the downward direction, a feather, when dropped with zero initial velocity, has its velocity vector directed in the direction of its acceleration.

If the downward direction is taken as positive, the falling feather can be said to have a positive velocity and a positive acceleration.

5 0

3 years ago

An elevator together with its passengers weights 5000 N. At a certain instant, the tension in its supporting cable is 6000 N. De

gayaneshka [121]

We have to forces acting on the system (elevator+passengers):
1) The weight (W=5000 N), acting downward
2) The cable's tension (T=6000 N), acting upward
So, the two forces have opposite direction. The resultant (in upward direction) will be
$F=T-W$
And for Newton's second law, the resultant of the forces acting on the system causes an acceleration on the system itself, given by
$a= \frac{F}{m}$
where m is the mass of the system.

So, we need to find F and m.
The resultant of the forces is
$F=T-W=6000 N-5000 N=1000 N$
To find m, we can use the weight of the system. In fact, the weight of an object is given by
$W=mg$
where $g=9.81 m/s^2$ . Solving for m, and using W=5000 N, we find
$m= \frac{W}{g}= \frac{5000 N}{9.81 m/s^2}=510 kg$

and at this point, we can calculate the acceleration of the system (elevator+people):
$a= \frac{F}{m}= \frac{1000 N}{510 kg}=1.96 m/s^2$
and the acceleration has the same direction of the resultant force, so upward.

8 0

3 years ago

as your roller coaster climbs to the top of the steepest hill on its track when does the first car have the greatest potential e

pochemuha

...the potential energy that you build while going up the hill on the roller coaster could be let go as kinetic energy -- the energy of motion that takes you down the hill of the roller coaster.

4 0

3 years ago

-A pool ball leaves a 0.70 meter high table with an initial velocity of 2.4 m/s. Predict the time required for the pool ball to

lorasvet [3.4K]

Answer:

0.70+2.4=23.7+35.0=answer

Explanation:

4 0

3 years ago

Read 2 more answers

A point charge of +1.0 µC is moved in the direction of an electric field, and it has a change in electric potential difference e

olga55 [171]

The answer of <span> the change in electric potential difference is</span> -1.0 × 10^7 V. It is defined as the work done per unit charge. A potential difference of 1 V means that 1 joule of work is done per coulomb of charge or 1 V = 1 J C-1.

7 0

2 years ago