C : perpendicular
The component of a vector are perpendicular
This is hard sorry but I need to anwser
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>
when plane is moving in head wind condition we will have
now when wind is tail wind condition during return journey we will have
time = 1 h 15 min = 1.25 hour
Now add both equations
Answer:
7.5 m/s²
Explanation:
Given:
v₀ = 0 m/s
v = 30 m/s
t = 4 s
Find: a
v = at + v₀
(30 m/s) = a (4 s) + (0 m/s)
a = 7.5 m/s²