Answer:
The speed of the block when it has returned to the bottom of the ramp is 6.56 m/s.
Explanation:
Given;
mass of block, m = 4 kg
coefficient of kinetic friction, μk = 0.25
angle of inclination, θ = 30°
initial speed of the block, u = 5 m/s
From Newton's second law of motion;
F = ma
a = F/m
Net horizontal force;
∑F = mgsinθ + μkmgcosθ
At the top of the ramp, energy is conserved;
Kinetic energy = potential energy
¹/₂mv² = mgh
¹/₂ v² = gh
¹/₂ x 5² = 9.8h
12.5 = 9.8h
h = 12.5/9.8
h = 1.28 m
Height of the ramp is 1.28 m
Now, calculate the speed of the block (in m/s) when it has returned to the bottom of the ramp;
v² = u² + 2ah
v² = 5² + 2 x 7.022 x 1.28
v² = 25 + 17.976
v² = 42.976
v = √42.976
v = 6.56 m/s
Therefore, the speed of the block when it has returned to the bottom of the ramp is 6.56 m/s.
Answer:
346819 Pa or ,347000 Pa in 3 significant figures
Explanation:
P1= 325000Pa , T1= 283K ,
P2=? T1= 302 K
as here volume and mass both are constant so using ratio method for pressure temperature law we have P1/T1 = P2/T2
THIS WE CAN ALSO OBTAIN BY RATIO METHOD FOR GENERAL GAS LAW AS
P1V1/(m1T1 ) = P2 V2/ (m2 T2)
IF V1 = V2 =V AND m1=m2=m then expression reduces to
P1/T1 = P2/T2
or P2 = (P1/T1)×T2
P2 = (325000/283) × 302
P2 = 1148.41×302
P2=346819
P2 = 347000 Pa in 3 significant figures
B. venus. although mercury is closest to the sun, venus is hotter, day & night. heat can escape mercury which is why it gets cold despite being so close to the sun. however venus is hottest because whenever heat gets there it never leaves due to the atmosphere venus has.
the answer is the speed of blue ball after collision is 2.6v
Answer:
0.1667Hz
Explanation:
by explanation frequency is given by 1/time
after carrying out the calculation of time we can easily get frequency.
time=speed/distance
=18/3
=6s
but frequency=1/time
hence=1/6
=0.1667hertz
