Answer:
W = 30 N
Explanation:
Applying the summation of torques about the wedge for equilibrium, taking the clockwise direction as negative. Since the ruler is balanced horizontally about the wedge. Therefore, the summation of all torques acting about the wedge must be equal to zero.
<u>W = 30 N</u>
Answer:
0.78 m
Explanation:
By the conservation of energy, the energy that they gain from potential energy, must be equal to the kinetic energy. So, for Adolf:
Ep = Ek
ma*g*ha = ma*va²/2
Where ma is the mass of Adolf, g is the gravity acceleration (10 m/s²), ha is the height that he reached, and va is the velocity. So:
100*10*0.51 = 100*va²/2
50va² = 510
va² = 10.2
va = √10.2
va = 3.20 m/s
Before the push, both of them are in rest, so the momentum must be 0. The system is conservative, so the momentum after the push must be equal to the momentum before the push:
ma*va + me*ve = 0, where me and ve are the mass and velocity of Ed. So:
100*3.20 + 81ve = 0
81ve = 320
ve = 3.95 m/s
By the conservation of energy for Ed:
me*g*he = me*ve²/2
81*10*he = 81*(3.95)²/2
810he = 631.90
he = 0.78 m
Answer:
t = 1.099 s
Explanation:
given,
constant speed = 2.51 m/s
height of balloon above ground = 3.16 m
time elapsed before it hit the ground = ?
Applying equation of motion to the compass
using quadratic formula to solve the equation
t = 1.099 s, -0.586 s
hence, the time elapses before the compass hit the ground is equal to 1.099 s.
Answer:
2.89 hours
Explanation:
given :
Vo = 72 km/h
Vt = 90 km/h
S = 234 km
find : the time taken (t) = ?
solution :
2.a.s = Vt² - Vo²
2.a.(234) = 90²- 72²
468.a = 8100 - 5184
= 2916
a = 2916/468 = 6.23 km/h²
so,
t = (Vt-Vo) /a
= (90-72)/ 6.23
= 18/ 6.23
= 2.89 hours
