Answer:
True
Explanation:
Velocity is a vector, therefore it consists of two elements:
- A magnitude (also called speed), which is the ratio between the displacement of the object and the time taken
- A direction, which corresponds to the direction of motion of the object
Therefore, velocity can be describes as positive or negative, depending on the direction which has been chosen as positive. If we chose the positive x-axis as positive direction, therefore:
- if the object is moving to the right (positive x-direction), the velocity will be positive
- if the object is moving to the left (negative x-direction), the velocity will be negative
So, in this case, since the velocity of the cart is negative, it must be moving to the left.
Answer:
Zero
Explanation:
Work done is given by multiplying force and distance moved. The distance is moved both positive and negative and it's equal distance. Since force used is the same hence work
W=F*d+ (F*-d)=0
Therefore, total work done is zero
Explanation:
When plutonium - 239 undergoes an alpha decay, it produces uranium - 235 in the process.
A radioactive occurs when a nuclide spontaneously disintegrates due to instability to produce lighter atoms which the release of radiation and energy.
²³⁹₉₄Pu ⇒ ²³⁵₉₂U + ⁴₂He + energy
In a nuclear reaction, the mass and atomic numbers must always remain conserved. Nuclear reactions do not obey the law of conservation of matter and mass.
The mass number are the superscript before the symbol of the nuclide
The atomic number is the subscript.
The sum of the atomic number on the left hand side equals that on the right hand side. This goes for the mass number too.
learn more:
Balanced nuclear equation brainly.com/question/10094982
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(C)
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