Answer:
The constant k has the value. k = 8.99 × 10 9 N ⋅ m 2 /C 2.
I KNOW that you must have seen this formula before. It gives
the distance covered in a certain time of accelerated motion:
D = 1/2 A T²
Distance covered= (1/2) (Acceleration) (Time squared) .
The question gives us the acceleration and the time.
I've got a weird idea: Let's plug them into the formula. OK ?
Distance = (1/2) (10 m/s²) (10 sec)²
= (5 m/s²) (100 sec²)
= 500 meters .
Deep lake !
Answer:
Average speed of the car = 16.53 m.s
Explanation:
For first 5 seconds:
As the car starts from rest, so the initial speed of the car, u=0
Acceleration, a= 4 m/s^2
So, the final speed (speed at time, t=5 second)
v=u+at
v=0 + 4 x 5 = 20 m/s
Distance covered,

s=50 m
As the car maintained the constant speed of 20 m/s for the next 10 seconds.
Distance traveled in 10 seconds, d=20 x 10 =200 m
For the last 4 seconds:
The car slows down at the rate of 2.0 m / s ^ 2 from the speed of 20 m/s.
As the car slows down, so the acceleration will be negative, i.e a=-2 m/s^2

s=80-16=64 m.
Considering all three cases, the total distance covered=
=50+200+64=314 m
Total time= 5+10+4=19 s
So, the averate peed= Totat distance covered / total time taken
=314/19=16.53 m/s
the answer for this question is c
Answer:
9.949 m
Explanation:
From the question,
L' = L+LαΔT................. Equation 1
Where L' = New length, L = Original length, α = linear expansivity of Cu, ΔT = change in temperature
Given: L = 10 m, α = 0.00017 K⁻¹, ΔT = 50-80
L' = 10+10(0.00017)(50-80)
L' = 10-0.051
L' = 9.949 m
Hence the new legth of Cu is 9.949 m