Answer:
60
Explanation:
Translation -
A book weighing 12 N is balanced on a table. Knowing that the static friction coefficient is 0.5, how much is the friction force worth?
Friction force is
f = u * n
f = 0.5 * 12N
f = 60
Answer:
<em>600N.</em>
Explanation:
From the question, we are to calculate the net force acting on the car.
According to Newton's second law of motion:
F = ma
m is the mass of the car
a is the acceleration = change in velocity/Time
a = v-u/t
F = m(v-u)/t
v is the final velocity = 30m/s
u is the initial velocity = 20m/s
t is the time = 5secs
m = 300kg
Get the net force:
Recall that: F = m(v-u)/t
F = 300(30-20)/5
F = 60(30-20)
F = 60(10)
<em>F = 600N</em>
<em>Hence the net force acting on the car is 600N.</em>
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Technically this is a Biology question;
The 'amount' we can see depends on how much light can get through our pupil to hit our retina.
When there is a lot of light the pupil is small; it doesn't need to be big to let a lot of light in.
When we move to a dark space there is much less light, so the pupil 'dilates' to let enough light so we can see properly.
The period in which one cant see is simply when the pupil hasn't had time to change shape yet so doesn't let in enough light.<span />