Galileo’s experiment showed that if two bodies of unequal masses are dropped from the same height, the time required by them to reach the ground are equal. If they are thrown vertically upwards with the same initial velocity, then the ratio of the time required to reach the ground is equal to unity. This means that both of them will reach the same height.

Correct Option: C

Galileo’s experiment showed that if two bodies of unequal masses are dropped from the same height, the time required by them to reach the ground are equal. If they are thrown vertically upwards with the same initial velocity, then the ratio of the time required to reach the ground is equal to unity. This means that both of them will reach the same height.

On average, seawater in the world’s oceans has a salinity of about 3.5% (35 g/L, or 599 mM). Seawater is denser than both fresh water and pure water (density 1.0 g/ml ) because the dissolved salts add mass without contributing significantly to the volume. The density of sea water is high due to impurities and salts compared to river water as a result; the upthurst produced by the sea water on the ship is more than that of river water. When a ship enters a sea from a river ,the ship is elevated or uplifted due to the density of sea water and during the buoyant motion of the ship, as it would gain both potential and kinetic energy when rising in the fluid.

Correct Option: A

On average, seawater in the world’s oceans has a salinity of about 3.5% (35 g/L, or 599 mM). Seawater is denser than both fresh water and pure water (density 1.0 g/ml ) because the dissolved salts add mass without contributing significantly to the volume. The density of sea water is high due to impurities and salts compared to river water as a result; the upthurst produced by the sea water on the ship is more than that of river water. When a ship enters a sea from a river ,the ship is elevated or uplifted due to the density of sea water and during the buoyant motion of the ship, as it would gain both potential and kinetic energy when rising in the fluid.

Diffuse sky radiation is solar radiation reaching the Earth’s surface after having been scattered from the direct solar beam by molecules in the atmosphere. Of the total light removed from the direct solar beam by scattering in the atmosphere (approximately 25% of the incident radiation when the sun is high in the sky, depending on the amount of dust and haze in the atmosphere), about two-thirds ultimately reaches the earth as diffuse sky radiation. The sunlit sky is blue because air scatters short-wavelength light more than longer wavelengths. Since blue light is at the short wavelength end of the visible spectrum, it is more strongly scattered in the atmosphere than long wavelength red light. The result is that the human eye perceives blue when looking toward parts of the sky other than the sun.

Correct Option: C

Diffuse sky radiation is solar radiation reaching the Earth’s surface after having been scattered from the direct solar beam by molecules in the atmosphere. Of the total light removed from the direct solar beam by scattering in the atmosphere (approximately 25% of the incident radiation when the sun is high in the sky, depending on the amount of dust and haze in the atmosphere), about two-thirds ultimately reaches the earth as diffuse sky radiation. The sunlit sky is blue because air scatters short-wavelength light more than longer wavelengths. Since blue light is at the short wavelength end of the visible spectrum, it is more strongly scattered in the atmosphere than long wavelength red light. The result is that the human eye perceives blue when looking toward parts of the sky other than the sun.

A transformer is a power converter that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer’s coils. A varying current in the primary winding creates a varying magnetic flux in the transformer’s core and thus a varying magnetic field through the secondary winding. This varying magnetic field induces a varying electromotive force (EMF), or “voltage”, in the secondary winding. This effect is called inductive coupling. The transformer is based on principle of mutual induction in which, firstly, that an electric current can produce a magnetic field (electromagnetism) and second that a changing magnetic field within a coil of wire induces a voltage across the ends of the coil (electromagnetic induction). Changing the current in the primary coil changes the magnetic flux that is developed. The changing magnetic flux induces a voltage in the secondary coil.

Correct Option: B

A transformer is a power converter that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer’s coils. A varying current in the primary winding creates a varying magnetic flux in the transformer’s core and thus a varying magnetic field through the secondary winding. This varying magnetic field induces a varying electromotive force (EMF), or “voltage”, in the secondary winding. This effect is called inductive coupling. The transformer is based on principle of mutual induction in which, firstly, that an electric current can produce a magnetic field (electromagnetism) and second that a changing magnetic field within a coil of wire induces a voltage across the ends of the coil (electromagnetic induction). Changing the current in the primary coil changes the magnetic flux that is developed. The changing magnetic flux induces a voltage in the secondary coil.

A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface. Since bicycle and wheelchair wheel spokes are only in tension, flexible and strong materials such as synthetic fibers, are also occasionally used. Metal spokes used in bicycles also increase the moment of inertia.

Correct Option: A

A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface. Since bicycle and wheelchair wheel spokes are only in tension, flexible and strong materials such as synthetic fibers, are also occasionally used. Metal spokes used in bicycles also increase the moment of inertia.