Because an object in rest stays in rest until an unequal force pushes it so gravity is pushing on the egg making it drop
Answer:
c. Joints allow the roadway to expand and contract as cars put force on the bridge
Explanation:
The reasons why joints are allowed on roadway is to accommodate the contraction and expansion of the road as cars put force on them.
- Most materials used in making roadways are susceptible to expansion and contraction.
- When a measure of force is applied their length either increases or decreases depending on the type of force.
- To accommodate these changes, joints are placed in roadways
Newton´s thrid law of motion states that:
Every action has an equal and opposite reaction.
c. equal, opposite.
Answer:
about 19.6° and 73.2°
Explanation:
The equation for ballistic motion in Cartesian coordinates for some launch angle α can be written ...
y = -4.9(x/s·sec(α))² +x·tan(α)
where s is the launch speed in meters per second.
We want y=2.44 for x=50, so this resolves to a quadratic equation in tan(α):
-13.6111·tan(α)² +50·tan(α) -16.0511 = 0
This has solutions ...
tan(α) = 0.355408 or 3.31806
The corresponding angles are ...
α = 19.5656° or 73.2282°
The elevation angle must lie between 19.6° and 73.2° for the ball to score a goal.
_____
I find it convenient to use a graphing calculator to find solutions for problems of this sort. In the attachment, we have used x as the angle in degrees, and written the function so that x-intercepts are the solutions.
<h3><u>Answer;</u></h3>
= 73 N
<h3><u>Explanation</u>;</h3>
Using the formula
2 T cos(30°) = w
Where; T is the tension on each string, while w is the weight of the box given by mg
Therefore;
W = 2Tcos 30°
= 2 × 42 cos 30°
= 84 cos 30°
= 72.74
<u> ≈ 73 N</u>
