Answer:
Color
Explanation:
Thus, for stars, considering them as “black bodies”, we can get an approximate figure for their temperature by measuring their dominant frequency (color). Technically scientists measure the brightness of the blue light and that of red light from the star, and from this they can calculate the temperature of the star.
Answer:
Elements in a period have wide range of chemical properties.
Explanation:
- Period is the row of chemical elements's arrangement in the periodic table. It is numbered from 1 to 7.
- In period as we move towards right the atomic number of element constantly increases along with the change in chemical properties.
- As we move from left towards right in period, the valence electron number regularly increases in every element.
- This valence electron differs the reactivity of the elements.
Answer: A Wavelength
Explanation: Because it’s wavelength
Answer is D.
Speed:
Use relative speed to simplify the situation. Since the trains are moving in opposite directions, you can add the speeds and pretend the first train is stationary (moving at 0m/s) and the second train is moving at 50m/s.
Distance:
The front of the second train needs to travel 120m to get from the front to the back of the first train. When the front of the second train is at the back of the first train, the back of the second train is still 10m in front of the first train. The back therefore has to travel 130m to clear the first train. The total distance over which the trains are overlapping in this scenario is therefore 120 + 130 = 250m.
You have speed and you have distance so now just calculate time:
v = d / t
50 = 250 / t
t = 5s
Explanation :
Density of an object can determine using mass and volume. We can measure mass and volume of various sports ball, both regular shaped ball and irregular shaped ball.
Density for regularly shaped ball and that of irregularly shaped ball is different.
Suppose that mass of an object is 100g and the volume is 
. So, using this data we can find density of that object as
