Answer:
The speed of the plank relative to the ice is:

Explanation:
Here we can use momentum conservation. Do not forget it is relative to the ice.
(1)
Where:
- m(g) is the mass of the girl
- m(p) is the mass of the plank
- v(g) is the speed of the girl
- v(p) is the speed of the plank
Now, as we have relative velocities, we have:
(2)
v(g/b) is the speed of the girl relative to the plank
Solving the system of equations (1) and (2)



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If each mL has 30 grams of the substance in it, then 60 mL have 1800 grams of mass in them. the weight of 1,800 grams of mass on Earth is (1.8 kg) x (9.8 m/s^2) = 17.6 newtons.
Answer:
∆h = 0.071 m
Explanation:
I rename angle (θ) = angle(α)
First we are going to write two important equations to solve this problem :
Vy(t) and y(t)
We start by decomposing the speed in the direction ''y''


Vy in this problem will follow this equation =

where g is the gravity acceleration

This is equation (1)
For Y(t) :

We suppose yi = 0

This is equation (2)
We need the time in which Vy = 0 m/s so we use (1)

So in t = 0.675 s → Vy = 0. Now we calculate the y in which this happen using (2)

2.236 m is the maximum height from the shell (in which Vy=0 m/s)
Let's calculate now the height for t = 0.555 s

The height asked is
∆h = 2.236 m - 2.165 m = 0.071 m
Answer:
the driving gear must be larger than the driven gear
Explanation:
Answer:
284.8 kgm/s
Explanation:
Impulse: This can be defined as the product of force and time of a body. The S.I unit of impulse is N.s mathematically.
Impulse = Force × time
Change in momentum: This is the product of the mass of a body and its change in velocity. The unit of change in momentum is kgm/s.
Mathematically,
momentum = mass×change in velocity
Deduction from newton's second law of motion,
Impulse = change in momentum
Therefore,
Change in Momentum = Force×time
ΔM = F×t................. Equation 1
Where F = force = 89 N, t =time = 3.2 s.
Substitute into equation 1
ΔM = 89×3.2
ΔM = 284.8 kgm/s
Thus the change in momentum = 284.8 kgm/s