The rock's height <em>y</em> at time <em>t</em> is given by
<em>y</em> = 45 m + (7.2 m/s) <em>t</em> - 1/2 <em>g</em> <em>t </em>²
where <em>g</em> = 9.80 m/s² is the magnitude of the acceleration due to gravity. Set <em>y</em> = 0 and solve for <em>t</em> :
0 = 45 m + (7.2 m/s) <em>t</em> - 1/2 <em>g</em> <em>t </em>² → <em>t</em> ≈ 3.9 s
Energy of a random atomic and molecular is called molecules energy
Answer:
The average velocity is
and respectively.
Explanation:
Let's start writing the vertical position equation :
Where distance is measured in meters and time in seconds.
The average velocity is equal to the position variation divided by the time variation.
= Δx / Δt =
For the first time interval :
t1 = 5 s → t2 = 8 s
The time variation is :
For the position variation we use the vertical position equation :
Δx = x2 - x1 = 1049 m - 251 m = 798 m
The average velocity for this interval is
For the second time interval :
t1 = 4 s → t2 = 9 s
Δx = x2 - x1 = 1495 m - 125 m = 1370 m
And the time variation is t2 - t1 = 9 s - 4 s = 5 s
The average velocity for this interval is :
Finally for the third time interval :
t1 = 1 s → t2 = 7 s
The time variation is t2 - t1 = 7 s - 1 s = 6 s
Then
The position variation is x2 - x1 = 701 m - (-1 m) = 702 m
The average velocity is
When the key is off there should be no current in the circuit.
Our ammeter still measures some current, and this is called hysteresis error. This means that this particular ammeter is going to add some amount of current to any current measured. In order to compensate for this error, we simply we deduct it from all measurements.
Each mark on the ammeter is worth:
This means that our error is:
When the circuit is closed we measure:
This is current with the error, real current in the circuit is:
<em>≈ 0.26 cm³</em>
<em>Hi there !</em>
<em>Gold is a metal with a very high density.</em>
<em>The density of gold is higher than that of lead.</em>
<em>Density(gold) = 19300 kg/m³ = 19.3 g/cm³</em>
<em />
<em>19.3 g ............ 1 cm³</em>
<em>5 g ..................x cm³</em>
<em>x = 5g×1cm³/19.3g = 0.2590 cm³ ≈ 0.26 cm³</em>
<em>Good luck ! </em>