Answer:
Explanation:
Before Thomson's discovery, atoms were believed according to the "Dalton's atomic theory" to be the smallest indivisible particle of any matter. This makes atoms the smallest unit of a matter.
Thomson in 1897, used the discharge tube to discover cathode rays which are today called electrons.
The discovery of electrons provided more light into the structure and nature of atoms. Atoms were now being seen in a different light as particles that are made up of other smaller sized particles.
Thomson through his experiment was able determine perfectly well the nature of the rays he saw emanating from the cathode. One of his findings shows that the rays are negatively charged and are repelled by negative charges.
The discovery of electrons further led to more works on the atom and other particles were discovered. Atoms were no longer seen as indivisible or the smallest particles of matter.
Newton's law of universal gravitation states that a particle attracts every other particle in the universe using a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them
Answer:
Before the plank will tip cat will walk 1.652 m
Explanation:
Mass of the cat along with plank 
Center of mass of the plank 
Mass of cat 
We have to find how far right of sawhorse B.
Plank will tip when weight of the cat about B is greater than the torque by the weight of the plank.
Balancing the the torque



There is too much information given, it's hard to understand exactly which variables are important in this problem.
Answer:
The following statements are correct.
1. The magnetic force on the current-carrying wire is strongest when the current is perpendicular to the magnetic field lines.
2. The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the field.
3. The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the current.
Wrong statements:
1. The magnetic force on the current-carrying wire is strongest when the current is parallel to the magnetic field lines.
Explanation: