Answer:
(1) A hot drink cooling to room temperature.
(2) The combustion of natural gas.
Explanation:
The spontaneous process is the process in which there is a release of energy and moves towards lower energy and a more thermodynamically stable energy state. All the natural processes are spontaneous.
There are two processes which are spontaneous in the given question are:
(1) A hot drink cooling to room temperature: In this, there is a decrease in energy and also it is a natural process and we know that all the natural processes are spontaneous.
(2) The combustion of natural gas: The fire is an example of an exothermic reaction. The combustion is a combination of a decrease in energy and an increase in entropy. So, this process occurs spontaneously.
Answer:
the speed limit 6 seconds and the car will travel in 90m
Answer:
Taking forces along the plane
F cos θ - M g sin θ -100 = M a net of forces along the plane
F = (M a + M g * .5 + 100) / .866 solving for F
F = (80 * 1.5 + 80 * 9.8 * .5 + 100) / .866 = 707 N
F = 707 N acting along the plane
Fn = F sin θ + M g cos θ forces acting perpendicular to plane
Fn = 707 * 1/2 + 80 * 9.8 * .866 = 1030 Newtons forces normal to plane
(this would give a coefficient of friction of 100 / 1030 = .097 = Fn)
Atomic mass = number of protons + number of neutrons = 4+5 = 9 amu
Angular acceleration = (change in angular speed) / (time for the change)
change in angular speed = (zero - 2,600 RPM) = -2,600 RPM
time for the change = 10 sec
Angular acceleration = -2600 RPM / 10 sec = -260 rev / min-sec
(-260 rev/min-sec) x (1 min / 60 sec) = <em>-(4 1/3) rev / sec²</em>
Since the acceleration is negative, the motor is slowing down.
You might call that a 'deceleration' of (4 1/3) rev/sec² .
The average speed is 1/2(2,600 + 0) = 1,300 rev/min = (21 2/3) rev/sec.
Number of revs = (average speed) x (time) = (21 2/3) x (10sec) = <em>(216 2/3) revs</em>
