Answer:
26.83 N.
Explanation:
If the angle between two vector is 90°, to get the resultant, we use Pythagoras theorem.
a² = b²+c²......................... Equation 1
Where a = R = Resultant, b = 12 N, c = 24 N.
Substitute these values into equation 1
R² = 12²+24²
R² = 144+576
R² = 720
√R² = √720
R = 26.83 N.
Hence, the result of the two force is 26.83 N.
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:
B and C
Explanation:
Because EMWs are varying magnetic and electric radiation traveling at 90° to each other propagating energy form one place to another through vibration of these magnetic and electric fields
Answer:
It was generally believed that mountains were produced by vertical forces
Explanation:
The main view of the world worked geologically prior to the 1960s was that the mountains were formed by the vertical forces of nature.
The early people prior to 1960s believed in many different natural phenomenons and they give their own reasons for their occurrence. But later many researchers and geophysicists studied the formation of the earth and came with possible answers to these questions.
Thus the answer is
" It was generally believed that mountains were produced by vertical forces."
Photosynthesis in plants converts solar energy into chemical energy using electrons and protons from water.