First, you find what 20% of 10 gallons of gas would be. This will show how many gallons the car actually uses.
10 gallons x 20% =
10 x 0.20 =
2 gallons used
Then you subtract that number from the total 10 gallons to get how many gallons of gas would be wasted.
10 gallons - 2 gallons =
8 gallons of gas wasted
Answer:
Explanation:
No of atoms of Ra in 1 g of sample = 6.023 x 10²³ / 226
N = 2.66 x 10²¹
disintegration constant λ = .693 / half life
half life = 1620 x 365 x 60 x 60 x 24 = 5.1 x 10¹⁰ s
disintegration constant λ = .693 / 5.1 x 10¹⁰
radioactivity dn / dt = λN
= (.693 / 5.1 x 10¹⁰ ) x 2.66 x 10²¹
= .3614 x 10¹¹ per sec
= 3.614 x 10¹⁰ / s
Answer:
0.976 c
Explanation:
= velocity of object 1 relative to earth = 0.80 c
= velocity of object 2 relative to object 1 = 0.80 c
= velocity of object 2 relative to earth
Velocity of object 2 relative to earth is given as


= 0.976 c
The atomic number gives you the number of protons element x has. Since the mass of protons and neutrons are almost similar(around 1 amu), the mass number can be thought of as the sum of protons and neutrons. so if element x whose atomic number is 40 has a mass number of 82, then we know that 42 of those must be neutrons.
Presumably, the ball is kicked parallel to the ground below the cliff, so its altitude <em>y</em> at time <em>t</em> is

where <em>g</em> = 9.80 m/s^2 is the acceleration due to gravity.
The ball hits the ground when <em>y</em> = 0:


