Answer:
126 kmh⁻¹
Explanation:
We can simply solve this by applying motion equations
where
v - final velocity
u - initial velocity
a-acceleration
t - time
v = u + at
= 25 + 5×2 = 35 ms⁻¹
= (35/1000)×3600 = 126 kmh⁻¹
Answer:
1/4
Explanation:
The period of a simple pendulum is:
T = 2π √(L/g)
At half the period:
T/2
= π √(L/g)
= 2π √(L/(4g))
= 2π √((L/4)/g)
So the length would have to be shortened by a factor of 1/4.
The acceleration of gravity is 9.81 m/s?.
If the upward acceleration of the bucket is
2.8 m/s², find the force exerted by the rope
on the bucket of water.
1. 69.658
2. 52.84
3. 85.318
4. 70.86
5. 84.429
Explanation:
Draw a free body diagram of the bucket. There are two forces:
Tension force T pulling up.
Weight force mg pulling down.
Sum of forces in the y direction:
∑F = ma
T − mg = ma
T = mg + ma
T = m (g + a)
Given m = 4.0 kg, g = 9.81 m/s², and a = 2.8 m/s²:
T = (4.0 kg) (9.81 m/s² + 2.8 m/s²)
T = 50.44 N