Answer:
Explanation:
From frequency of oscillation
Initially with the suspended string, the above equation is correct for the relation, hence
where k is force constant and m is the mass
When the spring is cut into half, by physics, the force constant will be doubled as they are inversely proportional
Employing f2/ f1, we have
Answer:
ΔT = 40.91 °C
Explanation:
First we find the kinetic energy of one hit to the nail:
K.E = (1/2)mv²
where,
K.E = Kinetic energy = ?
m = mass of hammer = 1.6 kg
v = speed of hammer = 7.7 m/s
Therefore,
K.E = (1/2)(1.6 kg)(7.7 m/s)²
K.E = 47.432 J
Now, for 10 hits:
K.E = (10)(47.432 J)
K.E = 474.32 J
Now, we calculate the heat energy transferred (Q) to the nail. As, it is the 59% of K.E. Therefore,
Q = (0.59)K.E
Q = (0.59)(474.32 J)
Q = 279.84 J
The change in energy of nail is given as:
Q = mCΔT
where,
m = mass of nail = 7.6 g = 0.0076 kg
C = specific heat capacity of aluminum = 900 J/kg.°C
ΔT = Increase in temperature = ?
Therefore,
279.84 J = (0.0076 kg)(900 J/kg.°C)ΔT
ΔT = (279.84 J)/(6.84 J/°C)
<u>ΔT = 40.91 °C</u>
Mass of car, M=2000kg
Velocity, V=72× 5/18 =20ms¹
Apply kinematic equation of motion
v² -u² = as
0 − 20² =2a×20
a=−10ms^-2
Breaking force, F=ma=2000×10=20 kN
Apply first kinematic equation
v = u +at
