Answer:
0.8m/s
Explanation:
Weight of mas,F=763 N
Mass of man=
By using 
Weight of flatcar=F'=3513 N
Mass of flatcar=
Total mass of the system=Mass of man+mass of flatcar=77.86+358.5=436.36 kg
Velocity of system=19.8m/s
Let v be the velocity of flatcar with respect to ground
Velocity of man relative to the flatcar=
Final velocity of man with respect to ground=v-4.68
By using law of conservation of momentum
Initial momentum=Momentum of car+momentum of flatcar
Initial speed of flatcar=Speed of system
Increase in speed=Final speed-initial speed=20.6-19.8=0.8m/s
Answer:
v doubles and f is unchanged
Explanation:
According to the formula v = f¶
Where v is the velocity of the wave
f is the frequency
¶ is the wavelength
Velocity is directly proportional to wavelength. Direct proportionality shows that increase in velocity will cause an increase in the wavelength and decrease in velocity will also cause a decrease in wavelength with the frequency not changing since the velocity and wavelength are both increasing and decreasing at the same rate.
According to the question, if the wavelength is doubled, the velocity (v) will also double while the frequency (f) remains unchanged.
Answer:
9) This is a case of deceleration
10)-0.8 ms-2
b) acceleration is the change in velocity with time
11)
a) 100 ms-1
b) 100 seconds
12) 10ms-1
13) more information is needed to answer the question
14) - 0.4 ms^-2
15) 0.8 ms^-2
Explanation:
The deceleration is;
v-u/t
v= final velocity
u= initial velocity
t= time taken
20-60/50 =- 40/50= -0.8 ms-2
11)
Since it starts from rest, u=0 hence
v= u + at
v= 10 ×10
v= 100 ms-1
b)
v= u + at but u=0
1000 = 10 t
t= 1000/10
t= 100 seconds
12) since the sprinter must have started from rest, u= 0
v= u + at
v= 5 × 2
v= 10ms-1
14)
v- u/t
10 - 20/ 25
10/25
=- 0.4 ms^-2
15)
a=v-u/t
From rest, u=0
8 - 0/10
a= 8/10
a= 0.8 ms^-2
Answer:
98 joules
Explanation:
1/2 of 28 = 14
14 multiply by 7= 98 joules
