Answer:
7.9
Explanation:
When we put the metal piece in the liquid (which is in the graduated cylinder), how much it goes up is equal to the volume of the piece we inserted.
So now we know that the volume of that piece of unknown metal is 7mL (which is the same as 7
).
Density is
.
So the density of that piece of metal is 
Which leaves us with a final density of 7.9
Answer:
4 A
Explanation:
We are given that

I=12 A
We have to find the current flowing through each resistor.
We know that in parallel combination current flowing through different resistors are different and potential difference across each resistor is same.
Formula :

Using the formula



Substitute the values



Hence, current flows through any one of the resistors is 4 A.
You'll hear that force called different things in different places. It
may be called "electromotive force", "EMF", "potential difference",
or "voltage".
It's just a matter of somehow causing the two ends of the wire
to have different electrical potential. When that happens, the
free electrons in the copper suddenly have a burning desire to
travel ... away from the end that's more negative, toward the end
that's more positive, and THAT's an "electric current".
Answer:
a) 



b) 
Explanation:
From the exercise we got the ball's equation of position:

a) To find the average velocity at the given time we need to use the following formula:

Being said that, we need to find the ball's position at t=2, t=2.5, t=2.1, t=2.01, t=2.001



--


--


--


b) To find the instantaneous velocity we need to derivate the equation


Answer:
a) 
Explanation:
From the question we are told that:
Open cart of mass 
Speed of cart 
Mass of package 
Speed of package at end of chute 
Angle of inclination 
Distance of chute from bottom of cart 
a)
Generally the equation for work energy theory is mathematically given by

Therefore




