Answer:
4.25 m/s
Explanation:
They walked the first distance at 5.50 m/s, then the same distance at 3 m/s.
Since the distances are equal, the average speed is simply the average of 5.50 and 3.
(5.50 + 3) / 2 = 4.25
Her average speed over the entire trip is 4.25 m/s.
Answer:
option (b)
Explanation:
Let the resistance of each resistor is R.
In series combination,
The effective resistance is Rs.
rs = r + R + R + .... + n times = NR
Let V be the source of potential difference.
Power in series
Ps = v^2 / Rs = V^2 / NR ..... (1)
In parallel combination
the effective resistance is Rp
1 / Rp = 1 / R + 1 / R + .... + N times
1 / Rp = N / R
Rp = R / N
Power is parallel
Rp = v^2 / Rp = N V^2 / R ..... (2)
Divide equation (1) by equation (2) we get
Ps / Pp = 1 / N^2
Answer:
To derive the fourth equation of motion, first we have to consider the equation for acceleration and then to rearrange it. or v2 = u2 + 2as and this equation of motion can be used to find the final velocity or the distance travelled if the other values are given.
Explanation:
v= u + at
s =( u + v ) t /2
s = ut + at2/2
v2 = u2 + 2as
The mechanical advantage of the screwdriver that is being described above is equal to 75N. This means that for every 30N that is applied on the screwdriver, this simple machine would in turn apply 75N of force to the lid of the can.
Zinc metal (Zn) reacts with sulfur (S) to create zinc sulfide (ZnS), and the chemical reaction is: Zn (s) + S (s) = ZnS (s).
Importance of Zinc (Zn) and sulfur (S):
- Zinc(Zn) is a vital element that our systems need to absorb food and nutrients as well as create healthy skin and bones. Zinc(Zn) ions play a crucial role in a number of the body's enzymes.
- Sulfur(S) is a pale yellow, tasteless, brittle solid that is also necessary for life. It is found in many proteins as well as the amino acids cysteine and methionine. It is a trace element found in bone minerals, bodily fluids, and lipids.
Chemical reaction -
In this experiment, heating a zinc(Zn) and sulfur(S) combination causes an interesting chemical reaction. A blinding flash of light, hot sparks, a hissing sound, and a cloud of white smoke in the shape of a mushroom are produced.
Therefore, the following chemical processes are taking place in the reaction: Zn (s) + S (s) = ZnS (s).
Learn more about Zinc(Zn) here:
brainly.com/question/13890062
#SPJ1