Answer:
Time elapsed = 2.856
SECOND ROCK HAS FASTER SPEED
Explanation:
This can be achieved in 2 ways, and it is clear from the careful study that the travel time is attributed to the time required to cross the path above the bridge by the 2nd stone i.e.
14 = 9.8 * t
t = 1.428 sec and
time between 2 splash = 2 * 1.428 = 2. 857 sec
2nd way
let time for 1st spalsh be t and
second splash be t1.
from equation of motion
so 60 = 14t + 0.5 * 9.8 * t * t
4.9 t^2 + 14t -60 = 0
On solving, we get t = 2.351 sec
for t_1, we have some extra time, which can be divided into t2 and t3.
14 = 9.8 * t2
t2 = 1.428 sec
total time taken by 2 is
T = 1.428 + 1.428 + 2.351
so we get t_1 = 5.207 sec
time elapsed is = T - t
= 5.207 - 2.351
Time elapsed = 2.856
SECOND ROCK HAS FASTER SPEED
Answer:
23.38 years
Explanation:
Speed of Allison = 0.83 c = v
Time passed according to Allison = Δt = 29.5 years
Time dilation

For Nora 52.88 years would have passed
So, their age difference would be 52.88-29.5 = 23.38 years
<h2>The K.E of the charge is 1.02 x 10⁻¹⁷ J</h2>
Explanation:
When the charge of 2e is placed in between the plates .
The force applied on this charge by plates is = q E
here q is the magnitude of charge = 2 e = 2 x 1.6 x 10⁻¹⁹ C
and E is the magnitude of electric field intensity
The work done = Force x displacement
Thus W = q E x S
here S is displacement
Therefore W = 2 x 1.6 x 10⁻¹⁹ x 4 x 8
= 1.02 x 10⁻¹⁷ J
This work will be converted into the kinetic energy of charge .
Thus K.E = 1.02 x 10⁻¹⁷ J
20 kg*m/s because there is 2 kg mass and 10 m/s so you can multiply.