Answer:
Keeping the speed fixed and decreasing the radius by a factor of 4
Explanation:
A ball is whirled on the end of a string in a horizontal circle of radius R at constant speed v. The centripetal acceleration is given by :

We need to find how the "centripetal acceleration of the ball can be increased by a factor of 4"
It can be done by keeping the speed fixed and decreasing the radius by a factor of 4 such that,
R' = R/4
New centripetal acceleration will be,




So, the centripetal acceleration of the ball can be increased by a factor of 4.
Answer:
The specific heat capacity of the zinc metal measured in this experiment is 0.427 J/g.°C
Explanation:
From the experimental data, the water loses heat because its initial temperature is greater than the final temperature of the mixture. On the other hand, the zinc metal gains heat because its initial temperature is less than the final temperature of the mixture
Heat loss by water = Heat gain by zinc metal
m1C1(T1 - T3) = m2C2(T3 - T2)
m1 is mass of water = 55.4 g
C1 is specific heat capacity of water = 4.2 J/g.°C
m2 is mass of zinc metal = 23.4 g
C2 is specific heat capacity of zinc metal
T1 is the initial temperature of water = 99.61 °C
T2 is the initial temperature of zinc metal = 21.6 °C
T3 is the final temperature of the mixture = 96.4 °C
55.4×4.2(99.61 - 96.4) = 23.4×C2(96.4 - 21.6)
746.9028 = 1750.32C2
C2 = 746.9028/1750.32 = 0.427 J/g.°C
Answer:
Motors convert electrical energy into mechanical energy
Explanation:
A motor uses electrical energy to create mechanical energy by creating magnetic fields causing the motor to spin. A generator is the opposite and converts mechanical into electrical by spinning a motor in a magnetic field.
Answer:

Explanation:
Assuming the we have to find ratio maximum forces on the mass in each case
we know that in a spring mass system
F= Kx
K= spring constant
x= spring displacement
Case 1:

case 2:

therefore, 
