Answer: m= 2.16 kg
Explanation: Momentum is expressed in the following formula:
p = mv
Derive to find m:
m = p / v
= 4.75 kg.m/s / 2.2 m/s
= 2.16 kg
Cancel out m/s and the remaining unit is in kg.
Answer:
a) 1450watts
b) 564watts
c) 1.11
Explanation:
Power consumed = IV
I is the current rating
V is the operating voltage
If a blow-dryer and a vacuum cleaner each operate with a voltage of 120 V and the current rating of the blow-dryer is 12 A, while that of the vacuum cleaner is 4.7 A then their individual power rating is calculated thus;
a) For blow-dryer
Operating voltage = 120V
Its current rating = 12A
Power consumed = IV
= 120×12
= 1440watts
b) For vacuum cleaner:
Operating voltage is the same as that of blow dryer = 120V
Its current rating = 4.7A
Power consumed = IV
= 120×4.7
= 564watts
c) Energy used = Power consumed × time taken
Energy used = Power × time
Energy used by blow dryer = 1440×20×60
= 1,728,000Joules
Energy used up by vacuum cleaner = 564×46×60
= 564×2760
= 1,556,640Joules
Ratio of the energy used by the blow-dryer in 20 minutes to the energy used by the vacuum cleaner in 46 minutes will be 1,728,000/1,556,640 = 1.11
Answer:
0.65 kg*m/s and 0.165 kg*m/s
Explanation:
Step one:
given data
mass m= 0.5kg
initial velolcity u=1.3m/s
final velocity v= 0.97m/s
Required
The change in momentum
Step two:
We know that the expression for impulse is given as
Ft= mv
Ft= 0.5*1.3
Ft= 0.65 kg*m/s
The expression for the change in momentum is given as
P= mΔv
substitute
Pt= 0.5*(1.3-0.97)
Pt= 0.5*0.33
Pt=0.165 kg*m/s
Answer:
Point C
Explanation:
Centripetal acceleration ac is inversely proportional to radius of orbit so it is greatest at point C.