Mass = PROTONS + neutrons. So, 19 +20 = 39.
(Don't confuse yourself between electrons and protons when they are equal because it could be an ion)
This is from dictionary: <span>a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
I would say it is 2</span>
Yeah this is option A one supercontinent
basically a long time ago we would have lived on pangea
Eventually this would split into two and we would get Gondwana and also Laurasia, so thechnically option two would be a possible choice but option A is the most possible choice.
Answer:
In the presence of UV light, ethane will react with bromine in a substitution reaction. UV light is the condition under which the reaction will occur so it is written above the arrow in the chemical equation. As the reaction proceeds, the intensity of the re-brown colour of the bromine water decreases.
Answer:
Explanation:
1. A measure of how quickly velocity is changing is the acceleration
Acceleration is the rate of change of velocity with time. The rate at which a body is changing its velocity is known as the acceleration.
It is measured in the unit m/s²
2. Speed in a given direction is the velocity
Velocity is a vector quantity which measures the magnitude of motion in a specific direction. It is simply speed in a given direction.
When we say a motorcycle travels at the rate of 5m/s due east, we are describing the velocity of such body.
3. Force that resists moving one object against another is the friction
Friction is a force that opposes motion. It prevents a body from moving.
4. Measure of the pull of gravity on an object Weight
Weight is a measure of the amount of gravitational force on a body. It is mathematically expressed as;
W = mg
W is the weight, m is the mass and g is the acceleration due to gravity
5 Tendency of an object to resist a change in motion is inertia
Inertia is the tendency of body to resist change in motion. It is the ability of a body to remain in a perpetual state of rest.
6 Size is the magnitude