Answer:
Explanation:
First, denote our known values;
Mass is impulse divided by change in velocity:
Hence, the mass of the ball is 141.30grams
Answer:
Approximately 
.
Explanation:
Cathode is where reduction takes place and anode is where oxidation takes place. The potential of a electrochemical reaction (
) is equal to
.
There are two half-reactions in this question. 
and 
. Either could be the cathode (while the other acts as the anode.) However, for the reaction to be spontaneous, the value of should be positive.
In this case, is positive only if is the reaction takes place at the cathode. The net reaction would be
.
Its cell potential would be equal to 
.
The maximum amount of electrical energy possible (under standard conditions) is equal to the free energy of this reaction:
,
where
is the number moles of electrons transferred for each mole of the reaction. In this case the value of is 
as in the half-reactions.
is Faraday's Constant (approximately 
.)
.
Answer:
microwaves
Explanation:
microwaves do emit radiation, technically speaking, but it's not the DNA-damaging radiation we're used to hearing about. Microwaves, along with radio waves from (you guessed it) radio and cell phone towers, are types of non-ionizing radiation.
Explanation:
In order to find out if the keys will reach John or not, we can use the formula of projectile motion to find the maximum height reached by the keys:
H = V²Sin²θ/2g
where,
V = Launch Speed = 18 m/s
θ = Launch Angle = 40°
g = 9.8 m/s²
Therefore,
H = (18 m/s)²[Sin 40°]²/(2)(9.8 m/s²)
H = 6.83 m
Hence, the maximum height that can be reached by the projectile or the keys is greater than the height of John's Balcony(5.33 m).
Therefore, the keys will make it back to John.
