Answer:
L= 1 m, ΔL = 0.0074 m
Explanation:
A clock is a simple pendulum with angular velocity
w = √ g / L
Angular velocity is related to frequency and period.
w = 2π f = 2π / T
We replace
2π / T = √ g / L
T = 2π √L / g
We will use the value of g = 9.8 m / s², the initial length of the pendulum, in general it is 1 m (L = 1m)
With this length the average time period is
T = 2π √1 / 9.8
T = 2.0 s
They indicate that the error accumulated in a day is 15 s, let's use a rule of proportions to find the error is a swing
t = 1 day (24h / 1day) (3600s / 1h) = 86400 s
e= Δt = 15 (2/86400) = 3.5 104 s
The time the clock measures is
T ’= To - e
T’= 2.0 -0.00035
T’= 1.99965 s
Let's look for the length of the pendulum to challenge time (t ’)
L’= T’² g / 4π²
L’= 1.99965 2 9.8 / 4π²
L ’= 0.9926 m
Therefore the amount that should adjust the length is
ΔL = L - L’
ΔL = 1.00 - 0.9926
ΔL = 0.0074 m
Force = change of momentum / time taken
Force = (90x3)/0.6
B. Kinetic energy increases, potential energy decreases.
Answer:
Impulse = 10.36 kg m/s
average force = 172.667 N
Explanation:
given data
mass = 0.280 kg
speed = 15.0 m/s
speed = 22.0 m/s
to find out
impulse and magnitude of the average force
solution
we know that Impulse is change in momentum that is
initial momentum = mass × speed ..........1
initial momentum = 0.28 × (15)
initial momentum = 4.2 kg m/s
Final momentum = mass × speed ..........2
Final momentum = 0.28 × (-22)
Final momentum = -6.16 kg m/s
so now we get Impulse that is
Impulse = 4.2 - (-6.16)
Impulse = 10.36 kg m/s
and
average force will be
average force = impulse ÷ time
average force = 
average force = 172.667 N
1. Changing from solid to a liquid is called melting / fusion and happen
at the melting/ fusion point.
Reason: melting point is a temperature at which a solid melt and converts into liquid by providing heat.
2. Changing from liquid to gas is called evaporation/boiling and happens at the evaporation/boiling point.
Reason. Evaporation is a process in which molecules from surface of liquid convert into gas.
3. Changing from a gas to a liquid is called condensation and happens at the condensation point.
Reason : In condensation process gas particles converts into liquid droplets.
4. Changing from liquid to a solid is called freezing and happens at the freezing point.
Reason : Freezing is a process that convert liquid into soilid state by decreasing temperature of that specific liquid,