When the velocity increases, then the acceleration will be positive and when the velocity decrease then the acceleration will be negative.
During the first hour, the velocity was 70 mph and during the seconds hour the velocity was 60 mph. Hence, the velocity decrease in the seconds hour. So, the acceleration will be negative during the second hour.
Now, during the third hour the velocity increases as it is 80 mph. Hence, the acceleration will be positive during the third hour.
Answer:

Explanation:
The resistance is given as

Where A IS Cross sectional area of wire
therefore resistivity \rho can be wrtten as

Putting all value to get resistivity value

Answer: 3. F1 = F2
Explanation:
According to <u>Newton's law of Gravitation</u>, the force
exerted <u>between two bodies</u> or objects of masses
and
and separated by a distance
is equal to the product of their masses divided by the square of the distance:
(1)
Where
is the gravitational constant
Now, in the especific case of the Earth and the satellite, where the Earth has a mass
and satellite a mass
, being both separated a distance
, the force exerted by the Earth on the satellite is:
(2)
And the force exerted by the satellite on the Earth is:
(3)
As we can see equations (2) and (3) are equal, hence the magnitude of the gravitational force is the same for both:

Answer:
Explanation:
Conclusion is simple you can just say that it is the value written in words form only.
Nothing else is written about it