According to the conservation of mechanical energy, the kinetic energy just before the ball strikes the ground is equal to the potential energy just before it fell.
Therefore, we can say KE = PE
We know that PE = m·g·h
Which means KE = m·g·h
We can solve for h:
h = KE / m·g
= 20 / (0.15 · 9.8)
= 13.6m
The correct answer is: the ball has fallen from a height of 13.6m.
1 pound ≈ 0.4536 kg
170 pounds ≈ 170 * 0.4536 kg
≈ 77.112 kg
Answer:
6
Explanation:
The median is found by listing the numbers in order numerically and finding the one that is right in the middle. In this case you have 1, 3, 5, 6, 7, 12, 15 where the middle term is 6.
Answer:
Industries outlook is uncertain
Explanation:
Competitive pressures stemming from the threat of entry are stronger when the industry's outlook is uncertain or highly risky, entry barriers are low, and very few existing industry members are looking to expand their market reach by entering product segments or geographic areas where they currently do not have a presence. entry barriers are low, the pool of entry candidates is large, and existing industry members are earning good profits. there are fewer than 10 entry candidates with the potential to hurdle the industry's barriers to entry. t is difficult or costly for a customer to switch to a new brand, the total dollar investment needed to enter the market successfully exceeds $5 million, and existing governmental regulations impose significant cost and compliance burdens on industry members. buyers have strong brand preferences and high degrees of loyalty to their preferred brand and when it takes new entrants less than 5 years to secure attractive amounts of space on retailers' shelves and build a well-recognized brand name.
Answer:
44.1 m
Explanation:
<u>Given:</u>
= speed of sound in air = 343 m/s
= speed of sound in the rod = 
= times interval between the hearing the sound twice = 0.12 s
<u>Assumptions:</u>
= length of the rod
= time taken by the sound to travel through the rod 
= time taken by the sound to travel to through air to the same point = 
We know that the distance traveled by the sound in a particular medium is equal to the product of the speed of sound in that medium and the time taken.
For traveling sound through the rod, we have
..........eqn(1)
For traveling sound through the air to the women ear for traveling the same distance, we have
Hence, the length of the rod is 44.1 m.
