Answer:
Momentum = 2qEx/v
Explanation:
From the work - energy theorem, we know that;
Kinetic energy = work done
Now, formula for both are;
Kinetic energy = ½mv²
Work done = qEx
Where;
m is mass
v is velocity
q is charge
E is Electric field
x is distance covered.
Thus;
½mv² = qEx - - - - (eq 1)
Now, momentum formula is;
p = mv
Let's rewrite the left hand side of equation 1 to reflect p = mv. Thus;
½v(mv) = qEx
½vp = qEx
p = 2qEx/v
Answer: B.Heat is never converted completely into mechanical energy.
Explanation:
According to the second principle of thermodynamics:
<em>"The amount of entropy in the universe tends to increase over time"
</em>
However the first formulation of this law (by Sadi Carnot) states:
<em>"There is an upper limit to the efficiency of conversion of heat to work, in a heat engine
"</em>
This means the heat cannot be completely transformed into mechanical energy in a machine. That is why a machine's effieciency is always less than 100%
Answer:
Work done on the car will be 548440.9463 J
Explanation:
We have given mass of the car m = 1075 kg
As the car finally stops so final velocity of the car
Initial velocity of car u = 115 km/hr
Work done is equal to change in kinetic energy
So work done
=
As the work done is negative so work is done on the car to stop it .
Answer : The rate constant for this reaction at 384.7 K is,
Explanation :
The relation between frequency factor, rate constant and activation energy for a chemical reaction is,
where,
k = rate constant = ?
A = frequency factor =
Ea = activation energy = 12.9 kJ/mol
T = temperature = 384.7 K
Now put all the given values in this formula, we get:
Therefore, the rate constant for this reaction at 384.7 K is,
Answer:
only animals are composed of cells is incorrect, the rest are part of the cell theory