Power = work/time = (Force times distance)/time
= (30N *10.0m)/5.00s = 300/5 = 60 Watts
Answer:
The potential difference between the places is 0.3 V.
∴ 1st option i.e. 0.3V is the correct option.
Explanation:
Given
Work done W = 3J
Amount of Charge q = 10C
To determine
We need to determine the potential difference V between the places.
The potential difference between the two points can be determined using the formula
Potential Difference (V) = Work Done (W) / Amount of Charge (q)
or

substituting W = 3 and q = 10 in the formula

V
Therefore, the potential difference between the places is 0.3 V.
∴ 1st option i.e. 0.3V is the correct option.
Answer:
(a) 89 m/s
(b) 11000 N
Explanation:
Note that answers are given to 2 significant figures which is what we have in the values in the question.
(a) Speed is given by the ratio of distance to time. In the question, the time given was the time it took the pulse to travel the length of the cable twice. Thus, the distance travelled is twice the length of the cable.

(b) The tension,
, is given by

where
is the speed,
is the tension and
is the mass per unit length.
Hence,

To determine
, we need to know the mass of the cable. We use the density formula:

where
is the mass and
is the volume.

If the length is denoted by
, then


The density of steel = 8050 kg/m3
The cable is approximately a cylinder with diameter 1.5 cm and length or height of 620 m. Its volume is




Answer:
Photoelectric-type alarms aim a light source into a sensing chamber at an angle away from the sensor. Smoke enters the chamber, reflecting light onto the light sensor; triggering the alarm.
Explanation:
nfpa.org is the website with theanswer