Answer:
0.75 m
Explanation:
Let's call the distance between the bulb and the mirror x.
The bulb and the length of the mirror form a triangle. The mirror and the illuminated area on the floor form a trapezoid. If we extend the lines from the mirror edge to the reflected image of the bulb, we turn that trapezoid into a large triangle. This triangle and the small triangle are similar. So we can say:
x / 0.4 = (3 + x) / 2
Solving for x:
2x = 0.4 (3 + x)
2x = 1.2 + 0.4 x
1.6 x = 1.2
x = 0.75
So the bulb should located no more than 0.75 m from the mirror.
Answer:
Explanation:
Initial height from the ground = .41 m
Final height = 1m
Height by which Kelli was raised ( h )= .59 m
When she passes through the lowest point , she loses P E
= mgh
= 440 x .59
= 259.6 J
kinetic energy possessed by her
= 1/2 mv²
= .5 x (440/9.8) x 2²
= 89.8 J
Difference of energy is lost due to work by air friction
work done by friction = 89.8 - 259.6
= - 169.8 J
The correct answer is C. Mercury and Mars have the same gravitational force
Explanation:
This chart compares the different features of two planets in our solar system (Mercury and Mars). In this chart, the only numerical value or feature that is the same for both planets is gravity because for both planets gravity is 1.7 m/s2. This implies the gravitational force or the force that attracts objects towards the center of the planet is the same or that objects are pulled with the same force in both planets. Moreover, this factor depends on others such as mass, density, among others.
Mass is the amount of matter in a material while weight is a measure of how the force of gravity acts upon the mass.