Constant speed along the inclined surface = 30 m / 4 s = 7.5 m/s
Vertical speed = inclined speed * sin(45) = 7.5 *√2 / 2 = 5.3 m/s
Answer: 5.3 m/s
<h2>Answer: Gravitational attraction
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Gravity force causes the clouds of dust and gas to form a protostar. As this <u>attraction force</u> is responsible for gathering and compressing the existing elements in the cloud of gas and dust, heating them during this process.
Then, when the amount of material accumulated by gravitational contraction is large enough, and the temperature and pressure reached high enough, the <u>nuclear fusion</u> process will begin.
To understand it better: The hydrogen nuclei will begin to fuse, generating helium nuclei in the process and releasing huge amounts of energy.
It should be noted that the protostars radiate half of the energy contributed by the gravitational collapse and the other half is invested in heating its core.
We need to consider for this exercise the concept Drag Force and Torque. The equation of Drag force is

Where,
F_D = Drag Force
= Drag coefficient
A = Area
= Density
V = Velocity
Our values are given by,
(That is proper of a cone-shape)



Part A ) Replacing our values,


Part B ) To find the torque we apply the equation as follow,



Answer:
F = 63N
Explanation:
M= 1.5kg , t= 2s, r = (2t + 10)m and
Θ = (1.5t² - 6t).
magnitude of the resultant force acting on 1.5kg = ?
Force acting on the mass =
∑Fr =MAr
Fr = m(∇r² - rθ²) ..........equation (i)
∑Fθ = MAθ = M(d²θ/dr + 2dθ/dr) ......... equation (ii)
The horizontal path is defined as
r = (2t + 10)
dr/dt = 2, d²r/dt² = 0
Angle Θ is defined by
θ = (1.5t² - 6t)
dθ/dt = 3t, d²θ/dt² = 3
at t = 2
r = (2t + 10) = (2*(2) +10) = 14
but dr/dt = 2m/s and d²r/dt² = 0m/s
θ = (1.5(2)² - 6(2) ) = -6rads
dθ/dt =3(2) - 6 = 0rads
d²θ/dt = 3rad/s²
substituting equation i into equation ii,
Fr = M(d²r/dt² + rdθ/dt) = 1.5 (0-0)
∑F = m[rd²θ/dt² + 2dr/dt * dθ/dt]
∑F = 1.5(14*3+0) = 63N
F = √(Fr² +FΘ²) = √(0² + 63²) = 63N