The first one is Force & the second one Power.
Answer:
Explanation:
The cross product of two vectors is given by

Where, θ be the angle between the two vectors and \widehat{n} be the unit vector along the direction of cross product of two vectors.
Here, K x i = - j
As K is the unit vector along Z axis, i is the unit vector along X axis and j be the unit vector along axis.
The direction of cross product of two vectors is given by the right hand palm rule.
So, k x i = j
j x i = - k
- j x k = - i
i x i = 0
The force that opposes motion to moving parts is F<span>riction</span><span>
Hope this helped!
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Answer:
Explanation:
Given that,
Mass of block
M = 2kg
Spring constant k = 300N/m
Velocity v = 12m/s
At t = 0, the spring is neither stretched nor compressed. Then, it amplitude is zero at t=0
xo = 0
It velocity is 12m/s at t=0
Then, it initial velocity is
Vo = 12m/s
Then, amplitude is given as
A = √[xo + (Vo²/ω²)]
Where
xo is the initial amplitude =0
Vo is the initial velocity =12m/s
ω is the angular frequency and it can be determine using
ω = √(k/m)
Where
k is spring constant = 300N/m
m is the mass of object = 2kg
Then,
ω = √300/2 = √150
ω = 12.25 rad/s²
Then,
A = √[xo + (Vo²/ω²)]
A = √[0 + (12²/12.5²)]
A = √[0 + 0.96]
A = √0.96
A = 0.98m