A shopping cart that starts from rest, is accelerated for 4 s, moves at constant velocity for 4 s, and is decelerated for 4s until returning to rest, has an average acceleration of 0 m/s².
A shopper is pushing a cart down a grocery store aisle. The movement of the cart is:
- It starts from rest.
- From t = 0 s to t = 4.0 s it is accelerated with a constant force.
- From t = 4 s to t = 8.0 s it receives just enough force to balance the friction on the cart.
- From t = 8 s to t = 12 s it is decelerated until it comes to rest.
All in all, at the initial time (t = 0 s), the velocity is 0 m/s (rest) and at the final time (t = 12 s) the velocity is 0 m/s as well (rest). The average acceleration in that period is:

A shopping cart that starts from rest, is accelerated for 4 s, moves at constant velocity for 4 s, and is decelerated for 4s until returning to rest, has an average acceleration of 0 m/s².
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Answer:
, repulsive
Explanation:
The magnitude of the electric force between two charged particles is given by Coulomb's law:
where:
is the Coulomb's constant
are the two charges of the two particles
r is the separation between the two charges
The force is:
- repulsive if the two charges have same sign
- Attractive if the two charges have opposite signs
In this problem, we have two electrons, so:
is the magnitude of the two electrons
is their separation
Substituting into the formula, we find the electric force between them:

And the force is repulsive, since the two electrons have same sign charge.
Answer:
57 %
Explanation:
input power = 16.4 kW = 16.4 x 10^3 W = 16400 W
Water pumped per second = 67 L/s
Mass of water pumped per second, m = Volume of water pumped epr second x density of water
m = 67 x 10^-3 x 1000 = 67 kg/s
height raised, h = 14 m
Output Power = m x g x h / t = 67 x 10 x 14 = 9380 W
efficiency = output power / input power = 9380 / 16400 = 0.57
% efficiency = 57 %
thus, the efficiency of the pump is 57 %.
Answer:
Honey how can i draw you cant draw here
Explanation:
I wish i can help you