Change in position (triangleV) divided by change in time (triangleT)
Answer:
B. Observation
Explanation:
Using a thermometer to read the temperature of a solution is tantamount to the making an observation.
Observation are recorded using our senses of sight, taste, earing, feeling etc or by the use of instrument.
- Through observation, data is usually collected to make inferences about an experiment.
- An observation leads to the formulation of a hypothesis which is scientific guess that leads to experimental designs.
- Conclusions are drawn from the information of data obtained from an experiment.
Answer:
The final velocity of the car A is -1.053 m/s.
Explanation:
For an elastic collision both the kinetic energy and the momentum of the system are conserved.
Let us call
= mass of car A;
= the initial velocity of car A;
= the final velocity of car A;
and
= mass of car B;
= the initial velocity of car B;
= the final velocity of car B.
Then, the law of conservation of momentum demands that

And the conservation of kinetic energy says that

These two equations are solved for final velocities
and
to give


by putting in the numerical values of the variables we get


and


Thus, the final velocity of the car A is -1.053 m/s and of car B is 3.49 m/s.
Answer:
Explanation:
Givens
Heat of Fusion = 2.05 * 10^5 J / kg watch the units.
Heat to actually melt the copper = 82 10^5 J
Formula
Mass of copper = Heat / Heat of Fusion
Solution
Mass of copper = 82*10^5 J / (2.05 * 10^5 J / kg)
Mass of copper = 40 kg
Notice that the kg is in the denominator of the second fraction. The rules of fractions would tell you the 1/1 / / 1 /kg . You take the right fraction and turn it upside down and multiply. 1 / 1 * kg/1 = 1* kg / 1*1 which is just kg.
Answer 40 kg of copper
<h2>Answer: Radio waves
</h2>
Radio waves are a type of electromagnetic radiation with wavelengths between 10 m to 10,000 m. In the electromagnetic spectrum this wavelength is longer than infrared light and therefore, it goes beyond the visible spectrum.
This type of electromagnetic waves is very well reflected in the ionosphere, the layer of the atmosphere through which they travel directly or using repeaters.
In addition, they are very useful to transport information, being important in telecommunications. They are used not only for conventional radio transmissions but also in mobile telephony and <u>TV</u>.
It should be noted that since radio signals have large wavelengths, they can be diffracted around certain obstacles, such as hills and mountain ranges, preventing the signal from reaching its destination.