
Explanation:
Given:


The cross product
is given by



First we need to turn Aouita's time for the race into seconds. There are
60 seconds in a minute, so 7 minutes and 29.45 seconds is (7 x 60) +
29.45 = 449.45. He ran 3000 meters in that time, so his average speed
was 3000 meters divided by 449.45 seconds. 3000 / 449.45 = 6.67 m/s. So,
on average, he covered 6.67 meters (more than 21 feet!) during each
second of the race.
Answer:
W = 16.5 Kj
P = 49.9 Watt
E = 16471
Explanation:
m = 73.5kg
t = 5min 30sec = (5×60) + 30 = 330sec
each step = 16.6cm = 0.166m
h = 135×0.166 = 22.41 m
g = 10 m/s²
(i) W = F × s = W × h = mgh
W = 73.5×10×22.41 = 16471.35
W = 16.5 Kj
(ii) Power = workdone/time
P = 16471.35/330
P = 49.9 Watt
(iii) The energy burnt in this process = 16471
The correct answer is B. The safety only prevents you from pulling the trigger, but does not stop the pin from striking the primer. For example, if you drop the firearm, the pin may hit the primer and fire the firearm. It is always responsible to keep the firearm pointed in a safe direction so that if this happens, no consequences come out of it.
Answer:
Explanation:
Force on a current carrying conductor in a magnetic field is given by the following expression
F = B i L where B is magnetic field perpendicular to wire or current , i is current and L is length of the wire.
Magnetic field of 1.5 x 10⁻⁵ T is making an angle of 60 degree with the wire so the component of field perpendicular to it
B = 1.5 X 10⁻⁵ Cos 30° = 1.3 x 10⁻⁵ T.
Force = BiL
= 1.3 X 10⁻⁵ X .4 X 1
= 5.2 X 10⁻⁶ N.
The direction of force can be found out from Fleming's left hand rule . It will be along downward direction.