Answer:
A. Two protons and two neutrons.
Explanation:
Alpha particles are positively charged specie identical to the nucleus of Helium atom.
Answer:
3.982 kg
Explanation:
The latent heat of vaporization = 540 cal/g
= 5.4 ×10⁵ cal/kg
L = 5.4 ×10⁵ × 4.19
= 2.26 × 10⁶ J/kg
Q = 12 × 750,000
= 9, 000, 000
= 9 × 10⁶ J
the maximum number of kg of water (at 100 degrees Celsius) that could be boiled into steam (at 100 degrees Celsius) is:
= 
= 3.982 kg
Answer:
Explanation:
Length if the bar is 1m=100cm
The tip of the bar serves as fulcrum
A force of 20N (upward) is applied at the tip of the other end. Then, the force is 100cm from the fulcrum
The crate lid is 2cm from the fulcrum, let the force (downward) acting on the crate be F.
Using moment
Sum of the moments of all forces about any point in the plane must be zero.
Let take moment about the fulcrum
100×20-F×2=0
2000-2F=0
2F=2000
Then, F=1000N
The force acting in the crate lid is 1000N
Option D is correct
0.616 is the distance from the top
of the building to the top of the window.
