Length of the copper rod = 2.5 meters
Speed at which sound travels through copper = 3560 meter per second
Let us assume the time taken
by sound to cover the given distance = x seconds
We already know that
Speed = Distance/ Time
Then
Time = Distance/ Speed
x = 2.5/3560 seconds
= 0.0007 seconds.
This can ve done by hitting one end of the rod and then receiving the sound at the other end and using the stop clock to measure the time taken.
Answer : Celestial or azimuth - altitude
Explanation :
Celestial : The celestial coordinates that are analogous to longitude and latitude are called RA and Dec.
RA = Right Ascension
Dec = Declination
RA is the measured in unit of time and Dec is measured in degree.
The equatorial coordinate system is the projection of the latitude and longitude coordinate system on the celestial sphere.
Azimuth - altitude : Azimuth - altitude define the location of an object in the sky.
The altitude is the distance of an object appears to be above the horizon.
The Azimuth of the object is the angular distance along the horizon to the location of the object.
Answer:
The answer is C)The force of gravity from Earth acting on the spacecraft decreased because the distance from Earth increased.
Explanation:
Gravity, a force, is dependent on the mass of the object exerting the gravity and the distance of an outside object from that object. The larger the object, the more gravity it will exert on an outside object. This force decreases as you move away from the object, but it will always still exist and never be equal to 0.
Some sort of magnetic metal
Metals are heavier per cubic unit than other materials such as air or water, and also are much more magnetic than other materials
To solve this problem it is necessary to apply the law of Malus which describes the change in the Intensity of Light when it crosses a polarized surface.
Mathematically the expression is given as

Where,
= Initial Intensity
I = Final Intensity after pass through the polarizer
= Angle between the polarizer and the light
Since it is sought to reduce the intensity by half the relationship between the two intensities will be given as

Using the Malus Law we have,





Angle with respect to maximum is 