Answer:
the Earth rotates on an imaginary line called its axis and different parts of the planet are facing towards the Sun or away from it. it takes 24 hours for the world to turn all the way around, and we call this a day.
Explanation:
Answer:
28 blocks
Explanation:
Amount: 21 + y
Ratio: 3:1
Total Ratio: 4
1 = yellow blocks
say if 3 is to 1 then 21 is to how many?
21 ÷ 3
= y = 7
= 21 + 7
= 28 blocks
( or you can use the practical method using your fingers )
Answer:
3.56x10^24 molecules
Explanation:
The following data were obtained from the question:
Mass of Na2SO4 = 840g
Molar Mass of Na2SO4 = (23 x2) + 32 + (16x4) =46 + 12 + 64 = 142g/mol
From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. This also gives that 1mole of Na2SO4 contains 6.02x10^23 molecules.
If 1 mole (i.e 142g) contains 6.02x10^23 molecules,
Therefore, 840g of Na2SO4 will contain = (840 x 6.02x10^23)/142 = 3.56x10^24 molecules
Answer:
R = 40 ohms
Explanation:
Given that,
The voltage of outlet, V = 120 V
Current flowing through the device, I = 3 A
We need to find the Resistance rating of the power cord. Let the resistance is R. We know that,
Ohm's law, V = IR
Put all the values,

So, the resistance rating of the power cord is equal to 40 ohms.
(I) kinetic energy of the boy when he hits the ground =potential energy
I. e ½mv²=mgh where g is 10ms-²
m=34kg, g=10ms² , h=3m
=34×10×3
=1020j
(i i) v²=u²+2gh
v²=0²+2×10×3
= 60
v=sqrt of 60