Answer:
25 m/s
Explanation:
from the question you van see that some detail is missing, however i found this same question using internet search engines on: 'https://www.chegg.com/homework-help/questions-and-answers/light-rail-passenger-trains-provide-transportation-within-cities-speed-slow-nearly-constan-q5808369'
here is the complete question:
'Light-rail passenger trains that provide transportation within and between cities speed up and slow down with a nearly constant (and quite modest) acceleration. A train travels through a congested part of town at 7.0m/s . Once free of this area, it speeds up to 12m/s in 8.0 s. At the edge of town, the driver again accelerates, with the same acceleration, for another 16 s to reach a higher cruising speed. What is the final Speed?'
SOLUTION
initial speed (u) = 7 m/s
final speed (v) = 13 m/s
initial acceleration time (t1) = 8 s
final acceleration time (t2) = 16 s
what is the higher cruising speed?
acceleration = 
acceleration =
= 0.75 m/s^{2}
since the train accelerates at the same rate, the increase in speed will be = acceleration x time (t2)
= 0.75 x 16 = 12 m/s
therefore the higher cruising speed = increase in speed + initial speed
= 12 + 13 = 25 m/s
<span>F* t = (m x v_final) - (m x v_initial)
200 x t = 50x8 - 50x0
t= 50 x 8 /200
t= 2s </span>
Answer: m = 0.035kg = 35g
Explanation: Momentum p=0.140kgm/s
Velocity v=4m/s
Mass m=?
Formula-
Momentum depends on the mass of the object in motion and its velocity.
The equation for momentum is
p = mv
m = p/v
m = 0.140/4
m = 0.035kg
m = 35g
Hence, in the toy dart gun mass of the dart is 0.035kg.
Explanation:
As per Rayleigh criterion, the angular resolution is given as follows:

From this expression larger the size of aperture, smaller will be the value of angular resolution and hence, better will be the device i.e. precision for distinguishing two points at very high angular difference is higher.