Answer:
20 meters.
Explanation:
In the graph, the x-axis (the horizontal axis) represents the time, while the y-axis (the vertical axis) represents the distance.
If we want to find the distance covered in the first T seconds, you need to find the value T in the horizontal axis.
Once you find it, we draw a vertical line, in the point where this vertical line touches the graph, we now draw a horizontal line. This horizontal line will intersect the y-axis in a given value. That value is the total distance travelled by the time T.
In this case, we want to find the total distance that David ran in the first 4 seconds.
Then we need to find the value 4 seconds in the horizontal axis. Now we perform the above steps, and we will find that the correspondent y-value is 20.
This means that in the first 4 seconds, David ran a distance of 20 meters.
Answer:
B. less
Explanation:
acceleration due to gravity on Earth, g = 9.8 m/s²
acceleration due to gravity on Moon, g = 1.6 m/s²
Given mass of the object as, m = 5 kg
Weight of an object is given as, W = mg
Weight of the object on Earth, W = 5 x 9.8 = 49 N
Weight of the object on Moon, W = 5 x 1.6 = 8 N
Therefore, the object weighs less on the moon compared to its weight on Earth.
The correct option is "B. less"
Using the formula: ΔY = V₀y * t + (1/2) * ay * t²
Solve for time and get: 1.968s
Then use: v = d/t in the x-direction and get: d = 3.936
<h2>
Answer: 502.08 J</h2>
Explanation:
The heat (thermal energy) needed in to raise the temperature in a process can be found using the following equation:
(1)
Where:
is the heat
is the mass of the element (<u>water</u> in this case)
is the specific heat capacity of the material. In the case of water is
is the variation in temperature <u>(which is increased in this case)</u>
Knowing this, let's rewrite (1) with these values:
(2)
Finally:
The equivalent resistance of resistors connected in parallel is

In our problem, we have 5 identical resistor of resistance

, so their equivalent resistance is

The problem also says that the equivalent resistance is

, so we can find the resistance R of each piece of wire:

In the initial wire, it's like the 5 pieces are connected in series, so the equivalent resistance of the wire is just the sum of the resistances of the 5 pieces: