Answer:
20.42 N/m
Explanation:
From hook's law,
F = ke ......................... Equation 1
Where F = Force applied to the spring., k = spring constant, e = extension.
Make k the subject of the equation,
k = F/e ................. Equation 2
Note: The force on the spring is equal to the weight of the mass hung on it.
F = W = mg.
k = mg/e................ Equation 3
Given: m = 250 g = 0.25 kg, e = 37-25 = 12 cm = 0.12 m.
Constant: g = 9.8 m/s²
Substitute into equation 3
k = (0.25×9.8)/0.12
k = 20.42 N/m.
Hence the spring constant = 20.42 N/m
Answer:
<em>The change of momentum of the dart is 0.84 Nw.s</em>
Explanation:
<u>Impulse and change of momentum</u>
The change in momentum of an object is its mass times the change in its velocity:

The change in the momentum can also be found by considering the force acting on it. If a force F acts for a time Δt, the change of momentum is given by:

The dart hits a dashboard with a net force of 14 N during the collision and stops in 0.06 seconds. The change of momentum is:

The change of momentum of the dart is 0.84 Nw.s
Answer:
The correct answer is 24.
Explanation:
Answer:
≈ 22¢
Explanation:
240 / 1000 = 0.240 kV
0.240 kV(2.5 A)(3 hr) = 1.8 kW•hr
1.8 kW•hr($0.12/kW•hr) = $0.216
The force pushing down is the force of Gravity. On a chair it is in perfect balance with the force pushing up (the normal force)
in terms of magnitude
FN = FG = mg
the forces are in opposite direction
hope this helps