Answer:
Explanation:
The velocity of the wrench must be equal to the velocity of the truck . So momentum of the wrench before it hits the wall
= mv = 6 x 13.3 = 79.8 kg m /s
If resisting force of wall be F , impulse on the wrench = F x time
= F x .07
Impulse = change in momentum of the wrench = mv - 0 = mv = 79.8 kgm/s
So F x .07 = 79.8
F = 1140 N .
Answer: the work done by the force is 0
Explanation:
F (x², xy)
121 = 11²
so R = x² + y² = 11²
p = x². Q = xy
Δp/Δy = 0, ΔQ/Δx
using Green's theorem
woek = c_∫F.Δr = R_∫∫ ΔQ/Δx - Δp/Δy) ΔA
= (x² + y² = 121)_∫∫ yΔA
now let x = rcosФ, y = rsinФ
ΔA = rΔrΔФ
so r from 0 to 11
and Ф from 0 to 2π
= 0_∫^2π 0_∫^11 rsinФ × rΔrΔФ
= 0_∫^2π SinФΔФ 0_∫^11 r²Δr
= [ -cosФ]^2π_0 [r³/3]₀¹¹ = ( -cos2π + cos0) (11³/3) = 0
therefore the work done by the force is 0
The height need to change by 4 to double the final velocity.
<h3>Final velocity of the object</h3>
The final velocity of an object during a free fall is related to maximum height of fall as given the equation below.
v = √2gh
v² = 2gh
v²/h = 2g
v₁²/h₁ = v₂²/h₂
when v₂ = 2v₁, change in height is calculated as;
h₂ = h₁v₂²/v₁²
h₂ = (h₁ (2v₁)²) / (v₁)²
h₂ = 4h₁v₁² / v₁²
h₂ = 4h₁
Thus, the height need to change by 4 to double the final velocity.
Learn more about final velocity here: brainly.com/question/25905661
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Answer:
Lenz's law
Explanation:
it states that induced emf of different polarities induces a current whose magnetic field opposes the change in magnetic flux through the coil in order to ensure that original flux is maintained through the coil when current flows in it.
according to Faraday' s law of electromagnetic induction
Where -ve sign due to lenz's law
Emf is the induced voltage also known as electromotive force
N is the number of loops.
dϕ Change in magnetic flux.
dt Change in time.
A force is a push or pull upon an object resulting from the object's interaction with another object.