Answer:

Explanation:
Given data
Flight distance S=4890 km
Time difference Δt=t₂-t₁=40 min
Air speed of plane=980 km/h
To find
Speed of jet stream
Solution
When moving in the same direction as the jet stream time taken as t₁=d/(v+vs),v is velocity of plane and vs is velocity of plane
While moving in opposite direction t₂=d/(v+vs)
So

Apply quadratic formula to solve for vs
So
Answer:
a)10.28 Nm
b)9.93 Nm
Explanation:
Let g = 9.81m/s2. First we can calculate the weight of the trophy
W = mg = 1.6 * 9.81 = 15.696 N
(a) The torque is product of force and its moment arm
T = WL = 15.696 * 0.655 = 10.28 Nm
(b) Suppose his arm makes an angle of 15 degree with respect to the horizontal line. We can still calculate the arm length, or the horizontal distance from the trophy to the champion:

Again, torque is product of force and its moment arm

About 1.3 SECONDS.............
The heat of fusion is the amount of energy required to change the state of one mole of substance from solid to liquid at constant temperature. Therefore, in order to determine the energy needed by a given mass of substance, we must first convert the mass into moles by using:
Moles = mass / Mr
Moles = 5.67 / 71.84
Moles = 0.079 mol
Energy = latent heat of fusion * moles
Energy = 32.2 * 0.079
Energy = 2.544 kJ = 2,544 J