Answer:
-80 J
Explanation:
The first law of thermodynamics states that:
where
is the change in internal energy of the system
Q is the heat absorbed by the system
W is the work done by the system
In this problem, we have:
Q = -30 J is the heat released by the system (negative because the system releases it)
W = +50 J is the work done by the system on the surrounding (positive since it is done by the system)
Therefore, the change in internal energy is
Answer:
The speed will be "3.4×10⁴ m/s²".
Explanation:
The given values are:
Angular speed,
w = 7200 rpm
i.e.,
=
=
Speed from the center,
r = 6.0 cm
As we know,
⇒ Linear speed,
On putting the estimated values, we get
Now,
Acceleration on disk will be:
⇒
Answer:
<em>The sea bed is 1125 m deep.</em>
Explanation:
<u>Speed</u>
It's the rate of change of the distance (d) traveled by an object over time (t).
The speed can be calculated by the formula:
It's known the speed of sound in water is v=1500 m/s. A sound wave is sent to the sea bed and bounces back to the ship 1.5 seconds later.
That is the time the wave takes to travel twice the distance from the ship to the sea bed, thus the required distance uses half of that time or t=1.5/2 = 0.75 seconds.
Solving the equation for d:
d = v.t
d = 1500 m/s * 0.75 s
d = 1125 m
The sea bed is 1125 m deep.
Answer:
Force = 485000 Newton.
Explanation:
Given the following data;
Mass = 485000 kg
Initial velocity = 20m/s
Final velocity = 25m/s
Time, t = 5 seconds
To find the force;
First of all, we would calculate the acceleration of the train i.e the rate of change of the velocity of the train with respect to time.
Mathematically, acceleration is given by the equation;
Where;
a is acceleration measured in
v and u is final and initial velocity respectively, measured in
t is time measured in seconds.
Substituting into the equation, we have;
Acceleration = (25 - 20)/5
Acceleration = 5/5
Acceleration = 1m/s²
Force is given by the multiplication of mass and acceleration.
Mathematically, Force is;
Force = mass * acceleration
Force = 485000 * 1
Force = 485000 Newton.