Answer:
50.4 N
Explanation:
Q1 = Q
Q2 = 4 Q
Distance = d
The force is given by

.... (1)
Now,
Q3 = 2 Q
Q4 = 7 Q
distance = d/3

.... (2)
Divide equation (2) by equation (1), we get
F' / 1.60 = 126 / 4
F' = 50.4 N
Thus, the force is 50.4 N.
Answer:
Q= -6900 J
Explanation:
use the formula Q=mC(T_2 - T_1) and sub in givens
Q=mC(T_2 - T_1)
Q= (200 g)(0.444 J/g°C)(22-100)
Q= -6900 J
The negative sign means heat is lost, which agrees with the decrease in temperature
Answer:
17 °C
Explanation:
From specific Heat capacity.
Q = cm(t₂-t₁)................. Equation 1
Where Q = Heat absorb by the metal block, c = specific heat capacity of the metal block, m = mass of the metal block, t₂ = final temperature, t₁ = Initial temperature.
make t₁ the subject of the equation
t₁ = t₂-(Q/cm)............... Equation 2
Given: t₂ = 22 °C, Q = 5000 J, m = 4 kg, c = 250 J/kg.°c
Substitute into equation 2
t₁ = 22-[5000/(4×250)
t₁ = 22-(5000/1000)
t₁ = 22-5
t₁ = 17 °C
The answer is D. As the ambulance gets closer, the sound waves are compressed relative to the person; so the frequency increases.