Answer:
32.3 m/s
Explanation:
The ball follows a projectile motion, where:
- The horizontal motion is a uniform motion at costant speed
- The vertical motion is a free fall motion (constant acceleration)
We start by analyzing the horizontal motion. The ball travels horizontally at constant speed of
and it covers a distance of
d = 165 m
So, the total time of flight of the ball is
In order to find the vertical velocity of the ball, we have now to analyze its vertical motion.
The vertical motion is a free-fall motion, so the ball is falling at constant acceleration; therefore we can use the following suvat equation:
where
is the vertical velocity at time t
is the initial vertical velocity
is the acceleration of gravity (taking downward as positive direction)
Substituting t = 3.3 s (the time of flight), we find the final vertical velocity of the ball:
Answer:
Explanation:
Heat required to raise the temperature
= mass x specific heat x rise in temperature
= .34 x 4200 x ( 95 - 23 )
= 102816 J .
1 kWh = 1000 x 60 x 60 J
= 3600000 J
102816 J = 102816 / 3600000
= .02856 kWh .
Answer:
During a chemical reaction, Bromine (Br) would be expected to <u><em>gain 1 valence electron to have a full octet.</em></u>
Explanation:
In the periodic table the elements are ordered so that those with similar chemical properties are located close to each other.
The elements are arranged in horizontal rows, called periods, which coincide with the last electronic layer of the element. That is, an element with five electronic shells will be in the fifth period.
The columns of the table are called groups. The elements that make up each group coincide in their electronic configuration of valence electrons, that is, they have the same number of electrons in their last.
The elements tend to resemble the closest noble gases in terms of their electronic configuration of the last layer, that is, having eight electrons in the last layer to be stable.
Bromine belongs to group 17 (VII A), which indicates that it has 7 electrons in its last shell. So bromine requires more energy to lose all 7 electrons and generate stability, than it does to gain 1 electron and fill in 8 electrons to be stable. So:
<u><em>During a chemical reaction, Bromine (Br) would be expected to gain 1 valence electron to have a full octet.</em></u>
Answer:
I think B) is uncorrect
Explanation:
As A) p=w/t so it's correct relation
C) power depend on time and work as work is distance multiple force so it refer to velocity
D) the powerful mean much work in a few time
