Answer:
a) W = - 318.26 J, b) W = 0
, c) W = 318.275 J
, d) W = 318.275 J
, e) W = 0
Explanation:
The work is defined by
W = F .ds = F ds cos θ
Bold indicate vectors
We create a reference system where the x-axis is parallel to the ramp and the axis and perpendicular, in the attached we see a scheme of the forces
Let's use trigonometry to break down weight
sin θ = Wₓ / W
Wₓ = W sin 60
cos θ = Wy / W
Wy = W cos 60
X axis
How the body is going at constant speed
fr - Wₓ = 0
fr = mg sin 60
fr = 15 9.8 sin 60
fr = 127.31 N
Y Axis
N - Wy = 0
N = mg cos 60
N = 15 9.8 cos 60
N = 73.5 N
Let's calculate the different jobs
a) The work of the force of gravity is
W = mg L cos θ
Where the angles are between the weight and the displacement is
θ = 60 + 90 = 150
W = 15 9.8 2.50 cos 150
W = - 318.26 J
b) The work of the normal force
From Newton's equations
N = Wy = W cos 60
N = mg cos 60
W = N L cos 90
W = 0
c) The work of the friction force
W = fr L cos 0
W = 127.31 2.50
W = 318.275 J
d) as the body is going at constant speed the force of the tape is equal to the force of friction
W = F L cos 0
W = 127.31 2.50
W = 318.275 J
e) the net force
F ’= fr - Wx = 0
W = F ’L cos 0
W = 0
Answer:
Explanation:
m = Mass of initial piece = 1.2 kg
= Velocity of toy in x direction = 0.05 m/s
= Velocity of toy in y direction = 0
= Velocity of fragment 1 in x direction = 0
= Velocity of fragment 1 in y direction = -0.9 m/s
= Velocity of fragment 2 in x direction
= Velocity of fragment 2 in y direction
= Mass of fragment 1 = 0.4 kg
= Mass of fragment 2 = 1.2-0.4 = 0.8 kg
Applying conservation of momentum in x axis
Applying conservation of momentum in y axis
From the above two final equations we get
The direction of the fragment 2 is
The velocity of fragment 2 is
Answer:
t₂ = t₁ / 5
Explanation:
Rotational kinematics using: ωf = ωi + αt
Starting from rest and speeding up:
ω₁ = 0 + αt₁ .. Eq1
Starting from ω₁ and slowing to a stop:
0 = ω₁ - 5αt₂
Substituting for ω₁ from Eq 1
0 = αt₁ - 5αt₂
5αt₂ = αt₁
5t₂ = t₁
t₂ = t₁ / 5
The time taken is approximately 26 minutes
Explanation:
The motion of the body in this problem is a uniform motion (= at constant velocity), therefore we can use the following equation:
where
v is the speed
d is the distance covered
t is the time taken
In this problem, we have
v = 75 km/h is the speed
d = 32 km is the distance to be covered
Solving for t, we find the time needed:
Converting into minutes,
Learn more about speed:
brainly.com/question/8893949
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