Answer:
The velocity of the ball is 0.92 m/s in the downward direction (-0.92 m/s).
Explanation:
Hi there!
The equation for the velocity of an object thrown upward is the following:
v = v0 + g · t
Where:
v = velocity of the ball.
v0 = initial velocity.
g = acceleration due to gravity (-9.8 m/s² considering the upward direction as positive).
t = time.
To find the velocity of the ball at t = 0.40 s, we have to replace "t" by 0.40 s in the equation:
v = v0 + g · t
v = 3.0 m/s - 9.8 m/s² · 0.40 s
v = -0.92 m/s
The velocity of the ball is 0.92 m/s in the downward direction (-0.92 m/s).
As we know that total work done by a force is given by


so it is product of force and displacement along same direction
as we can write it as

so it must be the product of force and displacement in same directions so correct answer must be
<u>B. in the same direction as the displacement vector and the motion.</u>
Answer:
C. The gravity acceleration is in the same direction as the force of gravity, and thus toward the center of the earth.
Explanation:
[ More info.- It doesn't affect the body when it is at the rest, and when it is in motion, it acts toward the center of the Earth and it's component is known as "Centripetal force" ]
UwU
Answer:
Explanation:
If you look closely, force 1 does not reach 0.2 until 0.4 force 2 reaches 0.2 at about 0.2 - hope that made sense :P
Answer:
b) N = 560 N, c) fr = 138.56 N, d) μ = 0.247
Explanation:
a) In the attachment we can see the free body diagram of the system
b) Let's write Newton's second law on the y-axis
N + T_y -W = 0
N = W -T_y
let's use trigonometry for tension
sin θ = T_y / T
cos θ = Tₓ / T
T_y = T sin θ
Tₓ = T cos θ
we substitute
N = W - T sin 30
we calculate
N = 640 - 160 sin 30
N = 560 N
c) as the system goes at constant speed the acceleration is zero
X axis
Tₓ - fr = 0
Tₓ = fr
we substitute and calculate
fr = 160 cos 30
fr = 138.56 N
d) the friction force has the formula
fr = μ N
μ = fr / N
we calculate
μ = 138.56 / 560
μ = 0.247