Answer:
B. 14.4 N
Rotational speed (Angular Velocity) = 2
The Radius of the circle = 1.2 m
Velocity = Angular velocity × radius = 2×1.2 = 2.4 m/s
Centripetal force= mv²/r = 3 × 2.4×2.4/1.2 = 3 × 2.4 × 2
= 14.4 N
Answer:
Sometimes Earth moves between the sun and the moon. When this happens, Earth blocks the sunlight that normally is reflected by the moon. (This sunlight is what causes the moon to shine.) Instead of light hitting the moon's surface, Earth's shadow falls on it.
Explanation:
I Just Know
Answer:
AC)=(AB)2+(BC)2−−−−−−−−−−−−√=42+32−−−−−−√
⇒displacement=16+9−−−−−√=25−−√=5m
-- The car starts from rest, and goes 8 m/s faster every second.
-- After 30 seconds, it's going (30 x 8) = 240 m/s.
-- Its average speed during that 30 sec is (1/2) (0 + 240) = 120 m/s
-- Distance covered in 30 sec at an average speed of 120 m/s
= <span> 3,600 meters .</span>
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The formula that has all of this in it is the formula for
distance covered when accelerating from rest:
Distance = (1/2) · (acceleration) · (time)²
= (1/2) · (8 m/s²) · (30 sec)²
= (4 m/s²) · (900 sec²)
= 3600 meters.
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When you translate these numbers into units for which
we have an intuitive feeling, you find that this problem is
quite bogus, but entertaining nonetheless.
When the light turns green, Andy mashes the pedal to the metal
and covers almost 2.25 miles in 30 seconds.
How does he do that ?
By accelerating at 8 m/s². That's about 0.82 G !
He does zero to 60 mph in 3.4 seconds, and at the end
of the 30 seconds, he's moving at 534 mph !
He doesn't need to worry about getting a speeding ticket.
Police cars and helicopters can't go that fast, and his local
police department doesn't have a jet fighter plane to chase
cars with.
The relationship between the resistance R of a wire and its resistivity
is given by
where L is the length of the wire and A is its cross sectional area.
In the problem, we have
,
and
. So we can solve the find the area A:
For a cylindrical wire, the cross sectional area is given by
where r is the radius. We know the value of the area A, so now we can find the radius of the wire:
