Answer: a) 11.76 m/s b) 7.056 m
Explanation:
The described situation is as follows:
An object is dropped from the top of a tower and when measuring the time it takes to reach the ground that turns out to be 0.02 minutes.
This situation is related to free fall, this also means we have constant acceleration, hence the equations we will use are:
(1)
(2)
Where:
Is the final velocity of the object
Is the initial velocity of the object (it was dropped)
is the acceleration due gravity
is the height of the tower
is the time it takes to the object to reach the ground
b) Begining with (1):
(3)
(4)
(5) This is the final velocity of the object
a) Substituting (5) in (2):
(6)
Clearing :
(7)
(8) This is the height of the tower
The first one is: head
Second one is: 10 trillion km
Think in gravity, the moon is orbiting the Earth because of gravitational pull/force. Without this gravitational pull, the moon will just move in a straight line (Newton's first law).
Ideal gas law:
PV = nRT
P = pressure, V = volume, n = # of moles, R = gas constant, T = temperature
Equipartition theorem:
Each degree of freedom that a molecule has adds 0.5kT to its total internal energy where k = Boltzmann's constant and T = temperature
2nd law of thermodynamics:
A set of governing principles that restrict the direction of net heat flow (always hot to cold, heat engines are never 100% efficient, entropy always tends to increase, etc)
Clearly the answer is Choice A
Answer:
1.90×10²⁰ Electrons
Explanation:
From the question,
Q = It.................... Equation 1
Where Q = charge flowing through the wire, I = current, t = time
Given: I = 4.35 A, t = 7.00 s
Substitute these values into equation 1
Q = 4.35(7.00)
Q = 30.45 C.
But,
1 electron contains 1.6×10⁻¹⁹ C
therefore,
30.45 C = 30.45/1.6×10⁻¹⁹ electrons
= 1.90×10²⁰ Electrons
