No, we cannot touch gravity nor can we physically see it. We can only see how it works.
Answer:
2.7%
Explanation:
Given:
Uncertainty of the speedometer (u)= 2.5km/h
Speed measured at that uncertainty (v) = 92km/h
Percent uncertainty (p) is given as the ratio of the uncertainty to the speed measured then multiplied by 100%. i.e
p =
%
p =
%
p = 2.7%
Therefore, the percent uncertainty is 2.7%
The simplest way to do this is to set up equivalent fractions, like this-

=

Solve for x by using cross multiplication.
40*2.2= 88
1*x=88
x=88
Therefore, the boy weighs 88lbs.
Power = work/time
= 500/10
= 50J/s or 50 watt
Answer:
c: long and thin resistor.
Explanation:
The resistance of a resistor is given by:
R = ρ*L/A
where:
R = resistance
ρ = resistivity (depends on the material)
L = length of the material
A = cross-sectional area of the material
We can see that the length is on the numerator, which means that if we increase the length, then the resistance is increased.
We also can see that the cross-sectional area is on the denominator, then if we increase the area (for example, with a ticker resistor) the resistance decreases.
Then if we want to maximize the resistance, we need to have a long and thin resistor, so the correct answer is c.