Answer:
16km/h
Explanation:
Vt=20km/h ---train speed
Vd=4km/h
Donas speed relative to ground is:
Vrd=Vt-Vd
Donas is moving in opposite direction of train .
Vrd=20km/h-4km/h
Vrd=16km/h
The right answer for the question that is being asked and shown above is that:
(1) <span>b. the light will reach the front of the rocket at the same instant that it reaches the back of the rocket.
</span>(2) <span>a. the light will reach the front of the rocket before it reaches the back of the rocket.
</span>(3) <span>b. less than Δt
</span>(4) <span>c. the length of your spaceship is getting longer.
(5) </span><span>c. 1.20c</span>
Total time = total distance / Average speed
Answer:
3.2N
Explanation:
Given parameters:
Mass of block = 1.5kg
Coefficient of kinetic friction = 0.6
Force of pull on block = 12N
Unknown:
Net force on the block = ?
Solution:
Frictional force is a force that opposes motion:
Net force = Force of pull - Frictional force
Frictional force = umg
u is coefficient of kinetic friction
m is the mass
g is the acceleration due to gravity
Frictional force = 0.6 x 1.5 x 9.8 = 8.8N
Net force = 12N - 8.8N = 3.2N
The final magnification will be 400-fold or 400 times the original size of the object.
For magnifying smaller objects, a compound microscope is used.
A compound microscope consists of an objective and an eyepiece, whose diagram is shown in the adjoining image.
The lens near the object is called an objective and the other one is the eyepiece.
Let the magnification of the objective be m1
Let the magnification of the eyepiece be m2
The final magnification by the microscope, M, will be
M = m1 x m2
Putting the values in the above equation
M = 40 x 10
M= 400
Thus, the final magnification will be 400-fold or 400 times the original size of the object.
To know more about "optical instruments", refer to the link given below:
brainly.com/question/13276240?referrer=searchResults\
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