Answer: yes it can be prevented
Explanation:
The sensation of weightlessness that astronauts experience seems to make their tasks almost effortless. However, as Newton's third law of motion suggests, working in space can be physically demanding.
As he tightens the bolt, he is rotating in the direction opposite to the bolt
It is possible if the handhold is designed in three dimensional motion where the astronaut motion will be the uplimb motion with the mass centre of hand move along circular helix trajectory
Angular momentum is conserved astronaut motion is conserved when net external torque is Zero.
1. <u>Some drawbacks of electron microscopes:</u>
- Price, size, repair, researcher learning and image artifacts arising from specimen preparation are the major drawbacks.
- This form of magnification is a massive, burdensome, costly piece of equipment, highly sensitive to vibration and exterior magnetic field.
- It must be held in an environment that is big enough to contain the microscope, as well as to secure and prevent any unwanted effect on the electrons.
- Upkeep includes ensuring balanced voltage supplies, electromagnetic coil / lens currents and cool water circulation so that the specimens are not destroyed or damaged by the heat released during the electrons energization process.
2. If an object being viewed under the phase-contrast microscope has the same refractive index as the background material than "it would be difficult to see because the phase contrast microscope amplifies differences in the refractive index".
<u>Explanation:</u>
In order to improve the comparison of transparent and colorless specimens with the light microscopy pictures, thus phase contrast is used. This allows the visualization of cells and cell elements which would be hard to see using a standard light magnification. The phase comparison does not involve the destruction, fixation or staining of cells.
Due to diffraction and scattering phenomena which exist at the edges of these objects, large, extended specimens are also quickly visualized with phase contrast optical. As light transits through one medium to another, the velocity is changed in proportion to the variations in the refractive index between the two media. Therefore, the wave is either increased or decreased in velocity whenever a coherent light wave produced by the oriented microscope filament progresses via a phase specimen with a particular thickness and refractive index.
Answer:
The height from which the rock was thrown is 1.92 m
Solution:
As per the question:
Speed with which the rock is thrown, v = 12.0 m/s
Horizontal distance traveled by the rock before it hits the ground, d = 15.5 m
Launch angle, 
Now,
To calculate the height, h from which the rock was thrown:
First, since we consider the horizontal motion in the trajectory of the rock, thus the time taken is given by:


Now,
The height from which the rock was thrown is given by the kinematic eqn, acceleration in the horizontal direction is zero:


Answer: True
Explanation:
Electromagnetic wave is defined as the wave which is associated with both electrical and magnetic component associated with them. They can travel in vacuum as well and travel with the speed of light.
Electromagnetic spectrum consists of electromagnetic waves called as radio waves, microwaves, infrared, Visible, ultraviolet , X rays and gamma rays in order of increasing frequency and decreasing wavelength.
Thus the statement that All light waves move through a vacuum with a constant speed is true.