Answer:
true
Explanation:
Area = πr²
Differentiating in respect to r
we get,
dA/dr = 2πr
using chain rule,
since r = 4feet
so ,
2π(4) = 8π
Answer:
For the first one c is the answer
For the second one c is also the answer
For the third one is b
Explanation:
I took that
Pressure is define as force per unit area. Mathematically expressed as,
P=F/A.
We are given, a mass of the ball equal to
m=1.6kg and an Area of 1.1cm2=1.1(
)m2
To calculate for the force exerted by the finger to the ball, it is simply equal to the weight of the ball. Mathematically,
F=W
Weight of the ball can be calculated as,
W= ma
where m=mass of the object and a is the acceleration due to gravity (9.8m/s).
Then, the Weight of the ball which is equalt to the force exerted by the finger,
W=F=(1.6 kg x 9.81)=15.696 N
Then Pressure would be,
P=(15.696N/1.1(.1(
)m2))
P=
142690.91 N/m2=142690.91 Pa
The average velocity of the whole journey will be total distance covered divided by the total time. It will be approximately equal to 8 m/s. The right answer is option B
<h2>VELOCITY</h2>
Velocity is the distance travelled in a specific direction. While the average velocity of the whole journey will be total distance covered divided by the total time
When driving a Toyota avensis car along a straight road for 16.5km at
50km/h,
The velocity = 50 km/h
Distance = 16.5 km
Use the speed formula to calculate time.
Speed = distance / time
Time = distance / speed
Time = 16.5 / 50
Time = 0.33 s
If over the next 20min, you walked another 2.5km further along the road for a petrol station, Then,
average velocity = Total distance covered divided by total time taken.
Where
The time t = 20/60 = 0.333 h
Total time = 0.33 + 0.3333
Total time = 0.6633333
Total distance = 16.5 + 2.5
Total distance = 19 km
Average velocity = 19 / 0.66333
Average Velocity = 28.64 km/h
Now convert Km/h to m/s
(28.6432 x 1000) / 3600
286432 / 3600
7.956m/s
Therefore, the average velocity of the whole journey from beginning of the drive to the arrival at the filling station will be approximately 8 m/s
Learn more about velocity here: brainly.com/question/6504879
Answer:
False
Explanation:
Something with high specific heat cooling down would take longer to heat up.