Bubbles came off from the copper pennies are hydrogen gas. There many free hydrogen ions in an acid like vinegar. And because of the chemical reaction between the copper and the vinegar, many hydrogen ions joined together to form hydrogen gas.
The answer is:
V = d/t d = 86 km t = 1.3 hrs
V = 86 km/ 1.3 hrs
V = 66.15 km/ hrs
I hope this helps!!
Answer:
The increase in the internal energy of the system is 360 Joules.
Explanation:
Given that,
Heat supplied to a system, Q = 292 J
Work done on the system by its surroundings, W = 68 J
We need to find the increase in the internal energy of the system. It can be given by first law of thermodynamics. It is given by :

So, the increase in the internal energy of the system is 360 Joules. Hence, this is the required solution.
Answer:
C) 100 joules
Explanation:
The kinetic energy of an object is given by:

where m is the mass of the object and v its speed.
In this problem, we have an object of mass m = 50 kg and v = 2 m/s, so by using the formula we can find its kinetic energy:

Answer:
Position-Time graphs display the motion of a object by showing the changes of velocity with respect to time.
The motion of a car on a position-time graph that is represented with a horizontal line indicates that the car has stopped moving.
A straight line with a positive slope indicates that the car is moving at a constant velocity, and thus the slope is constant. On the other hand, a curve with a changing slope, shows that the velocity is changing.