Answer:

negative sign indicates that the distance is decreasing with time
Explanation:
Let at any time t after noon that is 12 p.m.
distance traveled by car A = 40t
distance traveled by car B = 90-60t
then distance between the two cars at time t
............1
also, at time 1 p.m.
distance 
D=50 Km
differentiating equation 1 w.r.t. t we get

put t= 1 and D= 50 we get


Answer:
Explanation:
Given that the grand stone has initial angular velocity of
w(ini)= 6rad/
And it has a final angular velocity of
w(fin)=12.20rad/sec
Time taken is t=16s
Using equation of angular motion
To get angular acceleration (α)
w(fin)=w(ini)+αt
12.20=6+16α
16α=12.20-6
16α=6.2
α=6.2/16
α=0.3875rad/sec²
The angular acceleration is 0.39rad/s²
Angle that he turn using
w(fin)²=w(ini)²+2αθ
12.2²=6²+2×0.3875θ
12.2²-6²=0.775θ
0.775θ=112.84
Then, θ=112.84/0.775
θ=145.6radian
The angular displacement is 145.6rad
Answer:
C. Infrared and radio waves can pass through very dense materials without interference.
Explanation:
It was my study island question.
Explanation:
While studying the velocity of a cheetah over time in a spreadsheet program is given by :
y = 2.2 x + 1.2 ...(1)
We know that,
v=v₀+at ...(2)
v₀ is velocity when t = 0, v is velocity after time t, a is acceleration and t is time.
If we consider time t on x-axis and v on y axis, then only we can draw a plot of equation (2). On comparing equation (1) and (2) we get :
a = 2.2 (but it is not correct as we don't know about axes).
Hence, the correct option is (a) "We cant tell without knowing what was plotted on the horizontal and vertical axes"