Answer:
7.45 s.
Explanation:
Given:
h = 68.1 m
vi = 0 m/s
vf = 42.4 m/s
g = 9.81 m/s^2
Using,
h = vi*t +1/2*(a*t^2)
68.1 = 1/2 * (9.81*t^2)
t = sqrt((68.1*2)/9.81)
= 3.726 s.
Total time of flight = 2*t
= 2 * 3.726
= 7.45 s.
Answer: Scientists used relative dating and absolute dating.
Explanation:
Scientists used absolute dating to determine the actual number of years ago that events happened. They used relative dating to divide Earth's past into several time frames when similar organisms were on Earth.
Given :
A cell of e.m.f 1.5 V and internal resistance 2.5 ohm is connected in series with an ammeter of resistance 0.5 ohm.
To Find :
The current in the circuit.
Solution :
We know, resistance of the ammeter is in series with the circuit.
So, total resistance is :
R = 2.5 + 0.5 ohm
R = 3 ohm
Also, e.m.f applied is 1.5 V .
Now, by ohm's law :

Therefore, the current in the circuit is 0.5 A.
As charges move in a closed loop, they gain as much energy as they lose.
<h3>What is principle of
conservation of energy?</h3>
- According to the principle of conservation of energy, in a closed or isolated system, the total energy of the system is always conserved.
- The energy gained by the particles or charges in a closed system is equal to the energy lost by the charges.
Thus, we can conclude the following based on principles of conservation of energy;
- As charges move in a closed loop, they gain as much energy as they lose.
Learn more about conservation of energy here: brainly.com/question/166559