Answer:
Explanation:
If Tim jogs a distance of 7.2 km to the west and then he turns south and jogs 1.4 km, the resultant displacement of Tim is calculated using the pythagoras theorem as shown;
R² = 7.2²+1.4²
R² = 51.84+1.96
R² = 53.8
R = √53.8
R = 7.33 km
Hence the resultant of Tim's jog back to the beginning is 7.33km
For a concave mirror, the radius of curvature is twice the focal length of the mirror:
where f, for a concave mirror, is taken to be positive.
Re-arranging the formula we get:
and since the radius of curvature of the mirror in the problem is 24 cm, the focal length is
It goes into a supernova I think
Answer:
Mass will be the same
Explanation:
Mass does not change with gravity .... WEIGHT will be different, but not mass.
Answer:
vi = 3.95 m/s
Explanation:
We can apply the Work-Energy Theorem as follows:
W = ΔE = Ef - Ei
W = - Ff*d
then
Ef - Ei = - Ff*d <em> </em>
If
Ei = Ki + Ui = 0.5*m*vi² + m*g*hi = 0.5*m*vi² + m*g*hi = m*(0.5*vi² + g*hi)
hi = d*Sin 20º = 5.1 m * Sin 20º = 1.7443 m
Ef = Kf + Uf = 0 + 0 = 0
As we know, vf = 0 ⇒ Kf = 0
Uf = 0 since hf = 0
we get
W = ΔE = Ef - Ei = 0 - m*(0.5*vi² + g*hi) ⇒ W = - m*(0.5*vi² + g*hi) <em> (I)</em>
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If
W = - Ff*d = - μ*N*d = - μ*(m*g*Cos 20º)*d = - μ*m*g*Cos 20º*d <em>(II)</em>
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we can say that
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- m*(0.5*vi² + g*hi) = - μ*m*g*Cos 20º*d
⇒ vi = √(2*g*(μ*Cos 20º*d - hi))
⇒ vi = √(2*(9.81 m/s2)*(0.53*Cos 20º*5.1m - 1.7443 m)) = 3.95 m/s
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