These stars fuse helium into carbon just like the sun.
Given
Weight of the block A, Wa = 20 lb, weight of block B Wb = 50 lb. Applied
force to block A, P = 6lb, coefficient of static friction µs = 0.4, coefficient
of kinetic friction µk = 0.3. If a force P
is applied to the body, no relative motion will take place until the applied
force is equal to the force of friction Ff, which is acting opposite to the
direction of motion. Magnitude of static force of friction between block A and
block B, Fs = µsN, where N is
reaction force acting on block A. Now, resolve the forces Fx = max. P = (mA +
mB)a,
6 = (20 / 32.2 + 50 / 32.2)a
2.173a = 6
A = 2.76 ft/s^2
To check slipping occurs between block A and block B, consider block A:
P – Ff = mAaA
6 – Ff = 1.71
Ff = 4.29 lb
And also,
N = wA. We know static friction,
Fs = µsN
Fs = 0.4 x 20
Fs = 8lb
Frictional force is less than static friction. Ff < Fs
<span>Therefors, acceleration of block A, aA = 2.76 ft/s^2, acceleration of
block B aB = 2.76 ft/s^2</span>
Pressure at a given surface is given as ratio of normal force and area
so here force due to heel of the shoes is given as 80 N
and the area of the heel is given as 16 cm^2
so we can say

here we have
F = 80 N



so pressure at the surface due to its heel will be 5 * 10^4 N/m^2
Answer:
1)
Acceleration (a)=change in velocity/ change in time
Velocity (v)=90m/s
Time=0.0005s
a=90/0.0005
The acceleration =180000m/s^2 or 180km/s^2
Force = mass x acceleration
m=40g= 0.04kg
F= 0.04x 180000
F= 7200N or 7.2kN
Explanation: