Answer:
a ) = 381.48 J
b )= 84.25 cm
Explanation:
Kinetic energy of the runner
= 1/2 m v²
= .5 x 66 x 3.4²
= 381.48 J
The final kinetic energy of the runner is zero .
Loss of mechanical energy
= 381.48 J
This loss in mechanical energy is due to action of frictional force .
b )
Let s be the distance of slide
deceleration due to frictional force
= μmg/m
.7 x 66 x 9.8 / 66
a = - 6.86 m s⁻¹
v² = u² - 2 a s
0 = 3.4² - 2x6.86 s
s = 3.4² / 2x6.86
= .8425 m
84.25 cm
Forces occur in pairs and can be either balanced or unbalanced. Balanced forces do not cause a change in motion. Unbalanced Forces do cause a change in motion.
Answer:
both magnitude and direction
Explanation:
The worker's pull on the handle of the cart is best described as the force having both magnitude and direction.
- This is a vector quantity
- The force is channeled to move the cart in a specific direction.
- Also, the pull on the cart can be quantified, and so it have magnitude.
- Most physical properties either have magnitude or direction or both.
In this case, the worker is pulling the cart towards a specified direction.
Therefore, the fitting choice is both magnitude and direction.
If two charges are moved so that the distance between them is reduced
by half, then the forces between them become 4 times as strong.
D is the answer, you need look at the relates more to sound
