1.
1 answer:
Answer:
I guess you can round it to 11 seconds.
Explanation:
Going with a speed 9m/s means you are going 9 meters in each second.
If you are going 9 meters in second how many seconds will it take to 100 meters?
Visually;
9 meters - - - 1 second
100 meters - - - ?seconds.
When you write like this 9 times ?seconds equal to 100 meters time 1 second. (you probably know this but just in case)
So to find ?second you multiply 100meters by 1 and divide it by 9 whixh will give you 11.1111 seconds whixh again I believe you can round it to 11.
(Kind of a) Proof;
If 9m * ?sec = 100 m * 1 sec
you send 9 meters to other side.
?sec = (100 m * 1 sec) ÷ 9m
Hope it was clear and it helps! Please let me know if you have any questions.
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Answer:
D.
Explanation:
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t = thickness
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Answer:
B.The force of friction between the block and surface will decrease.
Explanation:
The force of friction is given by
where is the coefficient of friction and
is the normal force.
When the student pulls on the block with force at an angle
, the normal force on the block becomes
and hence the frictional force becomes
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Now, as we increase ,
increases which as a result decreases the normal force
, which also means the frictional force decreases; Hence choice B stands true.
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