21. A fisherman catches two sturgeons. The smaller of the two has a measured length of 93.46 cm (two dec- imal places and four s
1 answer:
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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
.
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.
<em>P.S: Choice D is tempting but incorrect since the weight </em><em> is independent of the external forces on the block. </em>
Answer:
<em>Explanation below</em>
Explanation:
<u>Speed vs Velocity </u>
These are two similar physical concepts. They only differ in the fact that the velocity is vectorial, i.e. having magnitude and direction, and the speed is scalar, just the magnitude regardless of the direction. They are strongly related to the concepts of displacement and distance, which are the vectorial and scalar versions of the space traveled by a moving object. The velocity can be computed as
Where is the position vector and t is the time. The speed is
To compute , we only need to know the initial and final positions and subtract them. To compute d, we need to add all the distances traveled by the object, regardless of their directions.
Maggie walks to a friend's house, located 1500 meters from her place. The initial position is 0 and the final position is 1500 m. The displacement is
and the velocity is
Now, we know Maggie had to make three different turns of direction to finally get there. This means her distance is more than 1500 m. Let's say she walked 500 m in all the turns, then the distance is
If she took the same time to reach her destiny, she would have to run faster, because her average speed is