<span>Z is present outside the solar system.</span>
Answer:
7800 J
Explanation:
Heat needed = mass of copper x specific heat of copper x change in temperature
Change in temperature = 30ºC - 20ºC = 10ºC
Specific heat of copper = 390 J/kgºC
Mass of copper = 2 Kg
Substituting the given values in above equation, we get –
Heat needed = 2 Kg x 390 J/kgºC x 10ºC
= 7800 J
Answer:
b. 2 m
Explanation:
Given that:
the identical speakers are connected in phases ;
Let assume ; we have speaker A and speaker B which are = 3 meter apart
An observer stands at X = 4m in front of one speaker.
If the amplitudes are not changed, the sound he hears will be least intense if the wavelength is: <u> </u>
From above; the distance between speaker A and speaker B can be expressed as:

The path length difference will now be:
= 5 m - 4 m
= 1 m
Since , we are to determine the least intense sound; the destructive interference for that path length will be half the wavelength; which is
= 
= 2 m
Answer:
gravity is the invisible force that attracts us the the earth\
1.normal force 2.frictional force 3. spring forces
flowing electrons produce a magnetic field
unbalanced forces are not equal they always cause changes in the moving object like the direction . balanced forces are equal and cause no changes
The SI system, also called the metric system, is used around the world. There are seven basic units in the SI system the meter kilogram second (s), kelvin the ampere , the mole and the candela.