Answer:
The rate of one is 2.1 mph and the rate of the other is 4.9 mph
Explanation:
Let the rate of one be y mph
The rate of the other = (y+2.8) mph
Total rate = y + y + 2.8 = (2y+2.8) mph
Total rate = distance apart/time
2y + 2.8 = 14/2
2y + 2.8 = 7
2y = 7 - 2.8
2y = 4.2
y = 4.2/2 = 2.1 mph
The rate of the other is y+2.8 = 2.1+2.8 = 4.9 mph
A nitrogen atom with 7 protons and 8 neutrons has a mass number of 15amu however on the periodic table the atomic mass for nitrogen is 14.01
Answer:
C. Zero for ammeter; infinity for voltmeter
Explanation:
Ammeter: A device that is used to measure the current through a circuit.
Voltmeter: A device that is used to measure the electric potential difference between two points in a circuit.
The relation among voltage (v), current (i), and resistance (r) is given as,
In ideal cases an ammeter must have zero resistance so that there is no voltage drop across it and accurate value of current will be measured.
In case of an ideal voltmeter, the resistance should be infinite so that the current across it is zero.
Suppose earth is a soid sphere which will attract the body towards its centre.So, acc. to law of gravitation force on the body will be,
F=G*m1m2/R^2
but we now that F=ma
and here accleration(a)=accleration due to gravity(g),so
force applied by earth on will also be mg
replace above F in formula by mg and solve,
F=G*mE*m/R^2 ( here mE is mass of earth and m is mass of body)
mg=G*mEm/R^2
so,
g =G*mE/R^2