You can just use basic
trigonometry to solve for the x & y components.
<span>vector a = 10cos(30) i +
10sin(30) j = <5sqrt(3), 5></span>
vector b is only slightly harder because the angle is relative
to vector a, and not the positive x-axis. Anyway, this just makes vector b with
an angle of 135deg to the positive x-axis.
<span>vector b = 10cos(135) i +
10sin(135) j = <-5sqrt(2), 5sqrt(2)></span>
So
now we can do the questions:
r = a + b
r = <5sqrt(3)-5sqrt(2), 5+5sqrt(2)>
(a)
5sqrt(3)-5sqrt(2)
(b)
5+5sqrt(2)
(c)
|r|
= sqrt( (5sqrt(3)-5sqrt(2))2 + (5+5sqrt(2))2 )
=
12.175
(d)
θ = tan-1 (
(5+5sqrt(2)) / (5sqrt(3)-5sqrt(2)) )
θ
= 82.5deg
<span> </span>
Answer:
a) t = 1.75 s
b) x = 31.5 m
Explanation:
a) The time at which Tom should drop the net can be found using the following equation:
Where:
: is the final height = 0
y₀: is the initial height = 15 m
g: is the gravity = 9.81 m/s²
: is the initial vertical velocity of the net = 0 (it is dropped from rest)
Hence, Tom should drop the net at 1.75 s before Jerry is under the bridge.
b) We can find the distance at which is Jerry when Tom drops the net as follows:
Then, Jerry is at 31.5 meters from the bridge when Jerry drops the net.
I hope it helps you!
Answer:
the work required to turn the crank at the given revolutions is 8,483.4 J
Explanation:
Given;
torque required to turn the crank, T = 4.50 N.m
number of revolutions, = 300 turns
The work required to turn the crank is given as;
W = 2πT
W = 2 x 3.142 x 4.5
W = 28.278 J
1 revolution = 28.278 J
300 revlotions = ?
= 300 x 28.278 J
= 8,483.4 J
Therefore, the work required to turn the crank at the given revolutions is 8,483.4 J
Answer:
Explanation:
The stunt will likely sustain serious injury in case of concrete blocks because the average force acting on the person will be more because concrete blocks do not squeeze to provide more time for the force to act on the body instead it acts for a small amount of interval.
As impulse is constant so time requires to act force on the body is more as compared to concrete block and thus average force in mattress case is less.
