The answer is B I took the test a while back
Answer:
a) t = 56.34 minutes
b) v = 5.32mph
c) t = 47.22 minutes
d) v = 6.35 mph
Explanation:
Given;
The speed of Ilya and Anya are
Run = 8.90mph
Walk = 3.80mph
distance = 5.00 miles
a) anya walk half the distance and run half the distance.
Speed = distance/time
time = distance/speed
t1 = 5×0.5/3.80 = 0.658hr
t2 = 5×0.5/8.90 = 0.281hr
t = t1 + t2 = 0.658+0.281 = 0.939hr × 60minutes/hr
t = 56.34 minutes
b) average speed = total distance/total time taken
v = 5.00miles/0.939hr = 5.32mph
c) Ilya walk half the time and run half the time.
t1 = t2 = t/2
Distance = speed × time
Substituting the values.
5 = 3.80(t/2) + 8.90(t/2)
5 = 12.70(t/2)
t = 10/12.70
t = 0.787 hr × 60 minutes/hr
t = 47.22 minutes
d) average speed = 5miles/0.787hr
v = 6.35 mph
Acceleration of block = net force/mass = 10/2 = 5 m/s²
When heat or any other kind of energy move from one place
to another, conduction and convection need some material stuff
along the way, otherwise they don't happen.
There is no material stuff between the Sun and the Earth, so
the Sun's energy reaches us by radiation.
Answer:
600 mC
Explanation:
The charge of an electron is 1.6 x 10-19C so for a current with 10 mA, the charge going to screen in one second is 10 mC
so number of electrons, n = (10 x 10-3)/(1.6 x 10-19) = 6.25 x 1016 so in a minute the charge is 10 * 60 = 600 mC