Answer:
(a) 2 (b) 4 (c) 4
Explanation:
Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.
Rules for significant figures:
- Digits from 1 to 9 are always significant and have infinite number of significant figures.
- All non-zero numbers are always significant. For example: 654, 6.54 and 65.4 all have three significant figures.
- All zero’s between integers are always significant. For example: 5005, 5.005 and 50.05 all have four significant figures.
- All zero’s preceding the first integers are never significant. For example: 0.0078 has two significant figures.
- All zero’s after the decimal point are always significant. For example: 4.500, 45.00 and 450.0 all have four significant figures.
- All zeroes used solely for spacing the decimal point are not significant. For example : 8000 has one significant figure.
As per question,
0.000054 has 2 significant figures.
3.001 x 10⁵ has 4 significant figures.
5.600 has 4 significant figures.
Answer:
Acceleration is 7.990487515m/s²
Initial velocity is 0m.s
Explanation:
s=ut+(1/2)at²
210=0(7.25)+(1/2)a(7.25²)
210=26.28125a
∴a=7.990487515m/s²
'Vi' or 'u' is the inital speed. Since it starts from rest, this equals 0.
Answer:
B. Acceleration in the direction of motion speeds you up
Explanation:
Acceleration is defined as when something gains speed. For example, when a car speeds up. Deceleration is when the car slows down, and looses speed. When defining these terms, think of a car going faster, then slowing down at a red light.
Since we have 15 kilometers per hour, and we're looking for 20 minutes, let's set up proportions.
20/60 minutes = x/15
20/60 = 1/3, so let's leave that simplified.
1/3 = x/15
Look at the denominators, 3 to 15 is a factor of 5, so multiply the numerator by 5.
1 • 5 = 5, so you will cover 5 kilometers in 20 minutes.
I hope this helps!
Answer:
linear charge density = -9.495 × 
C/m
Explanation:
given data
revolutions per second = 1.80 × 
radius = 1.20 cm
solution
we know that when proton to revolve around charge wire then centripetal force is require to be in orbit of radius around provide by electric force
so
- q × E = m × w² × r ..................1
- 9 × 
× 
q = m × w² × r ............2
and w = 
w = 
w = 1.80 × × 
w = 11304000 rad/s
so here from equation 2
- 9 × × 
1.80 × = 1.672 × 
× 11304000² × 0.0120
linear charge density = -9.495 × C/m
