Answer:
Sarah is right
Explanation:
This is an exercise that differentiates between scalars and vectors.
A scalar is a number, instead a vector is a number that represents the module in addition to direction and sense.
In this case, the distance (scalar) traveled is a number, which is why it is worth 1500m, but the displacement is a vector and since the point where it leaves is the same point where the vector's modulus arrives is zero, so the DISPLACEMENT VECTOR is zero
consequently Sarah is right
Answer:
Not be changed
Option: D
<u>Explanation:</u>
The physical quantity which has both ‘magnitude and direction’ is called vector. These vectors are represented by a line and an arrow, <em>the line represent the magnitude and arrow represent the direction of the physical quantity</em>. The vectors are added and subtracted according to the direction of the vectors.
According to the vector law addition while adding vectors direction and length of the vector is not be changed.<em> If the length of the vector changed the magnitude is also changed while so, while adding vectors length must not be changed.
</em>
Answer:
Explanation:
s = s₀ + v₀t + ½at²
s = 0 + 0(15) + ½(6)(15²)
s = 675 m
Not sure what the free fall acceleration is needed for, but if the object is dropped from a high enough point, it will travel in 15 seconds
s = ½10(15²) = 2250 m if air resistance is ignored
Answer:
The sound level will be 1.870 dB louder.
Explanation:
Given that,
Power = 130 W
Power = 200 W
We need to calculate the sound level
Using formula of sound level

For one amplifier,
...(I)
For other amplifier,
...(II)
For difference in dB levels




Hence, The sound level will be 1.870 dB louder.
Answer:

Explanation:
We know that heat relates to mass, specific heat and variation of temperature experimented because of this heat through the equation
. The heat released by the unknown material is absorbed by water, so we have
, and we can write:

Since thermal equilibrium is reached we know that
, where we have added
to convert the temperature from Celsius to Kelvin, as <em>we must do</em>. Since we want the specific heat of the unknown material, we do:

Which for our values is:
