Answer:
D
Explanation:
a neutron does not have a positive nor negative charge it remains neutral
Answer:
The velocity of the skateboard is 0.774 m/s.
Explanation:
Given that,
The spring constant of the spring, k = 3086 N/m
The spring is stretched 18 cm or 0.18 m
Mass of the student, m = 100 kg
Potential energy of the spring, 
To find,
The velocity of the car.
Solution,
It is a case of conservation of energy. The total energy of the system remains conserved. So,






v = 0.774 m/s
So, the velocity of the skateboard is 0.774 m/s.
Answer:
166 W
Explanation:
Power is the rate at which work is done.

The work done by Jill is the product of the weight of the pail and the height it moves.
The weight is the product of the mass and acceleration of gravity, <em>g</em>. Taking <em>g</em> as 9.81 m/s², the weight is
<em>W</em> = (6.90 kg)(9.81 m/s²) = 67.689 N
Work done = (67.689 N)(27.0 m) = 1827.603 J
Power = (1827.603 J) ÷ (11.0 s) = 166 W
Answer:
TEMPERATURE CHANGES
Explanation:
WELL ITS BASIC. WHEN TEMPERATURE CHANGES. IT MEANS THAT HEAT IS BEING TRANSFERRED AS I HEARD THAT COLD CANNOT BE TRANSFERRED
Answer:
145 m
Explanation:
Given:
Wavelength (λ) = 2.9 m
we know,
c = f × λ
where,
c = speed of light ; 3.0 x 10⁸ m/s
f = frequency
thus,

substituting the values in the equation we get,

f = 1.03 x 10⁸Hz
Now,
The time period (T) = 
or
T =
= 9.6 x 10⁻⁹ seconds
thus,
the time interval of one pulse = 100T = 9.6 x 10⁻⁷ s
Time between pulses = (100T×10) = 9.6 x 10⁻⁶ s
Now,
For radar to detect the object the pulse must hit the object and come back to the detector.
Hence, the shortest distance will be half the distance travelled by the pulse back and forth.
Distance = speed × time = 3 x 10^8 m/s × 9.6 x 10⁻⁷ s) = 290 m {Back and forth}
Thus, the minimum distance to target =
= 145 m