force in component form is given as
F~ = Fx ˆı + Fy ˆj
given that : Fx = 4 N, Fy = −3 N
hence the force equation looks like
F~ = 4 ˆı + (- 3) ˆj
F~ = 4 ˆı - 3 ˆj
displacement is given as
~s = sx ˆı + sy ˆj
given that : sx = 1 m, and sy = 1 m
hence the displacement is given as
~s = 1 ˆı + 1 ˆj
work done is the dot product of force and displacement . hence work done is given as
W = F~.~s
W = (4 ˆı - 3 ˆj) . (1 ˆı + 1 ˆj )
W = (4 x 1) ( ˆı.ˆı) - (3 x 1) (ˆj.ˆj)
W = 4 - 3
W = 1 J
θ = angle between F~ and ~s = ?
hence the work done by the force comes out to be 1 J
|F~| = magnitude of force = sqrt(Fx² + Fy²) = sqrt((4)² + (-3)²) = 5 N
|~s| = magnitude of displacement = sqrt(sx² + sy²) = sqrt((1)² + (1)²) = sqrt(2)
we know that work done is given as
W = |F~| |~s| Cosθ
1 = (5) (sqrt(2) Cosθ
Cosθ = 0.142
θ = Cos⁻¹(0.142)
θ = 81.84 deg
Answer is D.
Speed:
Use relative speed to simplify the situation. Since the trains are moving in opposite directions, you can add the speeds and pretend the first train is stationary (moving at 0m/s) and the second train is moving at 50m/s.
Distance:
The front of the second train needs to travel 120m to get from the front to the back of the first train. When the front of the second train is at the back of the first train, the back of the second train is still 10m in front of the first train. The back therefore has to travel 130m to clear the first train. The total distance over which the trains are overlapping in this scenario is therefore 120 + 130 = 250m.
You have speed and you have distance so now just calculate time:
v = d / t
50 = 250 / t
t = 5s
Earlier, we stated Newton's first law as “A body at rest remains at rest or, if in motion, remains in motion at constant velocity unless acted on by a net external force.” It can also be stated as “Every body remains in its state of uniform motion in a straight line unless it is compelled to change that state by forces
For example-A stationary object with no outside force will not move. With no outside forces, a moving object will not stop. An astronaut who has their screwdriver knocked into space will see the screwdriver continue on at the same speed and direction forever.
Answer:
divide 5000 ÷ 80 = 62.5 metros por minuto esa es la velocidad que alcanza la motocicleta para recorrer los 5 kilometros en 1.2 horas
Explanation:
5 kilometros conviertelos en metros (5kms. = 5000 metros) 1 km. = 1000 mts
1.2 horas conviertelos en minutos (1.2 hrs. = 80 minutos) 1 hora = 60 minutos, para sacar la fraccion de minutos divides 60 ÷ 6 = 10 minutos ( 10+10 = 20 minutos = .2 )