Where would you except to find the center of gravity of a plastic ruler
1 answer:
You might be interested in
Answer:
The potential energy of the more massive one is twice that of the other.
Explanation:
Potential energy is given by
<em>PE</em> = <em>mgh</em>
where <em>m</em> = mass of body, <em>g</em> = acceleration of gravity and <em>h</em> = height or elevation.
For the less massive car, let the mass be . Then its <em>PE</em> is
For the massive car, let the mass be . Its <em>PE</em> is
But
Hence, the potential energy of the more massive one is twice that of the other.
Answer:
a)
Explanation:
- Since the car speeds up at a constant rate, we can use the kinematic equation for distance (assuming that the initial position is x=0, and choosing t₀ =0), as follows:
- Since the car starts from rest, v₀ =0.
- We know the value of t = 5 sec., but we need to find the value of a.
- Applying the definition of acceleration, as the rate of change of velocity with respect to time, and remembering that v₀ = 0 and t₀ =0, we can solve for a, as follows:
- Replacing a and t in (1):
- Now, if the truck slows down at a constant rate also, we can use (1) again, noting that v₀ is not equal to zero anymore.
- Since we have the values of vf (it's zero because the truck stops), v₀, and t, we can find the new value of a, as follows:
- Replacing v₀, at and t in (1), we have:
- Therefore, as the truck travels twice as far as the car, the right answer is a).