The answers are B, C, E and F.
Atoms from an element is mostly made of protons, neutrons, and electrons. Proton numbers are like a class number for each element. Each element has their own and they're all different. And the number of protons are equal to the number of electrons. Therefore, B is correct.
Isotopes. It's different atoms from a same element that has the same number of protons but different number of neutrons. For example in hydrogen, there's 3 Isotopes for hydrogen. Therefore, C is correct.
Again, proton for the same element is never changed, even if they're different Isotopes. So, E is correct.
Isotopes, again, different elements may have different Isotopes. Some has only 1, others may have a few or more. So, F is correct too.
Answer:
I = 2.61 A
Explanation:
It is given that,
Power of a toaster is 300 watts
It is plugged into an outlet with a voltage of 115 volts
We need to find the current in the toaster's circuit.
The electrical power is given by the formula as follows :
P = V I
I is electric current
So, 2.61 A of current is in the toaster's circuit.
Answer:
the mass of the raft is 68.4 kg
Explanation:
Since Mass is defined as Volume times Density, start by calculating the volume of the raft:
Volume = length x width x high = 1.5 m x 1.0 m x 0.12 m = 0.18 m^3
and now multiply it times the given density in order to find its mass:
Mass = Volume x Density = 0.18 m^3 x 380 kg/m^3 = 68.4 kg.
Notice that the m^3 units cancel out (they are in numerator and in denominator) leaving just the kg (a unit of mass) in the answer.
Therefore, the mass of the raft is 68.4 kg
Answer:
a. 4.5secs
Explanation:
From the question, the equation describing the height is given by
at the point when the rock hit the ground, the height,h will be zero.
Hence we can have
hence the rock will hit the ground in 4.5secs
The correct answer is letter C. Volume is decreasing. For a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume<span> are </span>inversely proportional<span>. </span>
