Answer:
a)he angle is 90 with respect to the horizontal (x axis)
b) its speed is zero both vertically and horizontally
c) vertical path
d) a parabolic movement
e) v₀ = (9.5i ^ + 8.232 j ^) m / s
Explanation:
This is a relative problem and movement.
.v ’= v + u
Where v ’is the speed with respect to the mobile system, v the speed with respect to the fixed system and the speed between the two reference systems
a) The child and the can is in the truck, so they go at the speed of the truck, when he throws the can he continues at this speed on the x-axis and therefore as the two advance the same distance the more hands of the child, consequently the can is thrown vertically
The angle is 90 with respect to the horizontal (x axis)
b) with respect to the truck, the can is still, so its speed is zero both vertically and horizontally
c) The child sees that the can follows a vertical path
d) A stationary observer on the ground, sees that the can has a constant speed in the same direction of the truck and when they throw it vertical goal has a vertical movement, the sum of these two movements gives a parabolic movement of the same uncle as a projectile launch
e) the initial speed has two components
X Axis v_lata = v_camion = 9.5 m / s
Y Axis speed given by the child
Let's look for the travel time
x = v₀ₓ t
t = x / v₀ₓ
t = 16 / 9.5
t = 1.68 s
y = t - ½ g t²
When he returns to the child's hand and = 0
0 = v_{oy} t - ½ g t²
v_{oy} = ½ g t
v_{oy} = ½ 9.8 1.68
v_{oy} = 8,232 m / s
Speed is
v₀ = (9.5i ^ + 8.232 j ^) m / s
Answer:
The frequency shift detected is
Explanation:
From the question we are told that
The normal frequency of the state highway patrol radar guns
The speed of approach is
Now the frequency measure by the the state highway patrol radar guns as your car approaches is mathematically represented as
Where c is the speed of light which a has constant value of
Now
=>
substituting values
Answer:
The momentum, ΔP, and therefore, kinetic energy given to the ball in a serve is the result of the product of the tension force, 'F', in the string and the time of contact, Δt, between the ball and the string
ΔP = F × Δt
Explanation:
The impulse, ΔP, is the produce of the force, 'F', applied to a body for a given period of time, Δt', that gives motion to the body, and it is equal to the change of momentum of the body
ΔP = F × Δt
The momentum, 'P', of a body is the product of the mass, 'm', of the body and its velocity, 'v'
P = m × v
Tension is the axial pulling force of a string
T = Axial Force, F
The tension used in Tennis Racket strings is between 40 to 65 lbs.
When high tension is used in the string, the string is taut, and the contact duration between the Racket string and the ball is minimal, and the player needs to use more force to obtain a high momentum, and therefore, energy in the ball, which reduces control, and increase stress, as force is more emphasized
When low tension is used in the string, the Tennis Racket strings are more elastic. During a serve, the ball pushes the strings further back into the racket, such that the ball spends more time in contact with the string, (Δt is larger), and therefore, the impulse, F·Δt = ΔP, given to the ball is larger, therefore, the ball has a larger change in momentum, and therefore more energy in the intended direction.
However, a very slackened string will increase the increase area and time (large Δt) of contact of the ball and the racket such that the force given to the ball, F = ΔP/(large Δt) is reduced and therefore reduce the likelihood of gaining points from a serve against an opponent with a much forceful return of a serve.