From 50km/h to 0km/h in 0.5s we need next acceleration:
First we convert km/h in m/s:
50km/h = 50*1000/3600=13.8888 m/s
a = v/t = 13.88888/0.5 = 27.77777 m/s^2
Now we use Newton's law:
F=m*a
F=1700*27.7777 = 47222N
1) The mass of the continent is 
2) The kinetic energy of the continent is 274.8 J
3) The speed of the jogger must be 2.76 m/s
Explanation:
1)
The continent is a slab of side 5900 km (so the surface is 5900 x 5900, assuming it is a square) and depth 26 km, therefore its volume is:

The mass of the continent is given by

where:
is its density
is its volume
Substituting, we find the mass:

2)
To find the kinetic energy, we need to convert the speed of the continent into m/s first.
The speed is
v = 1.6 cm/year
And we have:
1.6 cm = 0.016 m

So, the speed is

Now we can find the kinetic energy of the continent, which is given by

where
is the mass
is the speed
Substituting,

3)
The jogger in this part has the same kinetic energy of the continent, so
K = 274.8 J
And its mass is
m = 72 kg
We can write his kinetic energy as

where
v is the speed of the man
And solving the equation for v, we find his speed:

Learn more about kinetic energy:
brainly.com/question/6536722
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Answer:
5 Days to Seconds = 432000
Explanation:
Answer:
This is known as a Galilean transformation where
V' = V - U
Where the primed frame is the Earth frame and the unprimed frame is the frame moving with respect to the moving frame
V - speed of object in the unprimed frame
U - speed of primed frame with respect to the unprimed frame
Here we have:
V = -15 m/s speed of ball in the moving frame (the truck)
U = -20 m/s speed of primed (rest) frame with respect to moving frame
So V' = -15 - (-20) = 5 m/s
It may help if you draw a vector representing the moving frame and then add
a vector representing the speed of the ball in the moving frame.
Answer:
hello your question is incomplete attached below is the complete question
answer :
a) I1 = I2
b) J1 > J2
c) E 1 > E2
d) ( vd1 ) > ( vd2 )
Explanation:
a) The currents in the two segments are the same i.e. I1 = I2 and this is because the segments are connected in series
b) Comparing the current densities J1 and J2 in the two segments
note : current density ∝ 1 / area
The area of the second segment is > the area of first segment therefore
J1 > J2
J1 ( current density of first segment )
J2 ( current density of second segment )
c) Comparing the electric field strengths E1 and E2
note : electric field strength ∝ current density
since current density of first segment is > current density of second segment and conductivity of the materials are the same hence
E 1 > E2
d) Comparing the drift speeds Vd1 and Vd2
( vd1 ) > ( vd2 )
this because ; vd ∝ current density